Agreed you won't need HO, HA prior to slotted Regen Aura and Adrenaline Boost should be more than enough, just need to stay close to each other. After those are slotted even HA will be largely moot, you'll 'heal' via regeneration not by getting 'healed'. You won't need Fitness and Stamina in particular. I'd strongly consider Leadership and Hasten. Since you are going with CJ+SJ that leaves one pool and an epic left. Concealment would do well for giving you the option to initiate combat on your terms (with Grant Invisibility), or Fighting for Tough and Weave making your regen go even further.
EDIT to add a build in ... hrmm notice you have swift, this build doesn't include swift but should give you some ideas. Basically I started by thinking well if HA isn't going to be all that needed but you have to take it anyway may as well make it work for you. Decided to grab as much +hit points in the build as I could. Ends up with an Empath pushing 1470 health, 65% S/L resists, capped defenses to everything (assuming Fort and Maneuvers from your duo), and assuming 1 Regen Aura plus AB from your duo partner, capped regen.
Hero Plan by Mids' Hero Designer 1.601
http://www.cohplanner.com/
Click this DataLink to open the build!
Emp_Sonic dedicated duo (v1.00.i16): Level 50 Magic Defender
Primary Power Set: Empathy
Secondary Power Set: Sonic Attack
Power Pool: Speed
Power Pool: Fighting
Power Pool: Leaping
Power Pool: Leadership
Ancillary Pool: Electricity Mastery
Hero Profile:
Level 1: Healing Aura -- Numna-Heal(A), Numna-Heal/EndRdx/Rchg(11), Numna-Heal/Rchg(11), Mrcl-Heal(23), Mrcl-Heal/Rchg(29), Mrcl-Heal/EndRdx/Rchg(29)
Level 1: Shriek -- Dev'n-Acc/Dmg(A), Dev'n-Dmg/Rchg(3), Dev'n-Hold%(9), Decim-Dmg/Rchg(21), Decim-Acc/Dmg/Rchg(31), Decim-Build%(31)
Level 2: Scream -- Dev'n-Acc/Dmg(A), Dev'n-Dmg/Rchg(3), Dev'n-Hold%(5), Decim-Dmg/Rchg(9), Decim-Acc/Dmg/Rchg(15), Decim-Acc/Dmg(31)
Level 4: Howl -- Posi-Acc/Dmg(A), Posi-Dmg/Rng(5), Posi-Dmg/Rchg(15), Det'tn-Dmg/Rng(21), Det'tn-Dmg/EndRdx/Rng(36)
Level 6: Hasten -- RechRdx-I(A), RechRdx-I(7), RechRdx-I(7)
Level 8: Boxing -- Acc-I(A)
Level 10: Clear Mind -- Range-I(A)
Level 12: Fortitude -- LkGmblr-Def(A), LkGmblr-Rchg+(13), LkGmblr-Def/Rchg(13), LkGmblr-Def/EndRdx/Rchg(23), Ksmt-ToHit+(36)
Level 14: Combat Jumping -- Zephyr-ResKB(A)
Level 16: Tough -- TtmC'tng-ResDam(A), TtmC'tng-ResDam/EndRdx(17), S'fstPrt-ResDam/Def+(17), TtmC'tng-ResDam/Rchg(25)
Level 18: Recovery Aura -- RechRdx-I(A), RechRdx-I(19), RechRdx-I(19)
Level 20: Weave -- LkGmblr-Def(A), LkGmblr-Def/EndRdx(25), LkGmblr-Rchg+(37), LkGmblr-Def/Rchg(50)
Level 22: Assault -- EndRdx-I(A)
Level 24: Maneuvers -- LkGmblr-EndRdx/Rchg(A), LkGmblr-Def(39), LkGmblr-Def/EndRdx(39), LkGmblr-Rchg+(50)
Level 26: Regeneration Aura -- Dct'dW-Heal(A), Dct'dW-Heal/EndRdx(27), Dct'dW-EndRdx/Rchg(27), Dct'dW-Heal/Rchg(36), Dct'dW-Heal/EndRdx/Rchg(37), Dct'dW-Rchg(37)
Level 28: Super Jump -- Zephyr-ResKB(A)
Level 30: Tactics -- AdjTgt-ToHit(A), AdjTgt-ToHit/Rchg(34), AdjTgt-ToHit/EndRdx/Rchg(40), AdjTgt-EndRdx/Rchg(40), AdjTgt-ToHit/EndRdx(46)
Level 32: Adrenalin Boost -- Dct'dW-Heal(A), Dct'dW-Heal/Rchg(33), Dct'dW-Heal/EndRdx/Rchg(33), Dct'dW-EndRdx/Rchg(33), Dct'dW-Rchg(34), Efficacy-EndMod/Rchg(34)
Level 35: Screech -- Stpfy-Acc/Stun/Rchg(A), Stpfy-Acc/Rchg(39), Stpfy-Stun/Rng(43), RzDz-Acc/Stun/Rchg(45), RzDz-Acc/Rchg(46), RzDz-Immob%(46)
Level 38: Dreadful Wail -- Oblit-Dmg(A), Oblit-Dmg/Rchg(40), Oblit-Acc/Dmg/Rchg(48), Oblit-Acc/Dmg/EndRdx/Rchg(50)
Level 41: Electric Fence -- Dev'n-Acc/Dmg(A), Dev'n-Dmg/Rchg(42), Dev'n-Hold%(42), HO:Centri(42), HO:Centri(43), TotHntr-Dam%(43)
Level 44: Charged Armor -- TtmC'tng-ResDam(A), TtmC'tng-ResDam/EndRdx(45), TtmC'tng-ResDam/Rchg(45)
Level 47: Power Sink -- P'Shift-EndMod(A), P'Shift-EndMod/Rchg(48), P'Shift-EndMod/Acc(48)
Level 49: Vengeance -- LkGmblr-Rchg+(A)
------------
Level 1: Brawl -- Empty(A)
Level 1: Sprint -- ULeap-Stlth(A)
Level 2: Rest -- Empty(A)
Level 1: Vigilance
Given that the lack of need for stamina and single target heals frees up your build quite a bit, it might be handy to have rez for those times you just screw up. I have an emp/sonic staminaless build, though he is built for regular team play. You could sub out the recall/tp for CJ/SJ, and perhaps take Shout instead of Heal other. Here is the basic framework of what I use anyhow:
Hero Plan by Mids' Hero Designer 1.601
http://www.cohplanner.com/
Click this DataLink to open the build!
Mr. Lincoln: Level 50 Science Defender
Primary Power Set: Empathy
Secondary Power Set: Sonic Attack
Power Pool: Teleportation
Power Pool: Speed
Power Pool: Leadership
Ancillary Pool: Power Mastery
Hero Profile:
Level 1: Healing Aura -- Dct'dW-Heal/EndRdx/Rchg(A), Dct'dW-Heal/Rchg(3), Dct'dW-EndRdx/Rchg(3), Dct'dW-Heal/EndRdx(5), Dct'dW-Heal(5)
Level 1: Shriek -- Decim-Acc/Dmg(A), Decim-Dmg/EndRdx(7), Decim-Dmg/Rchg(7), Decim-Acc/EndRdx/Rchg(9), Decim-Acc/Dmg/Rchg(9)
Level 2: Heal Other -- Dct'dW-Heal(A), Dct'dW-Heal/EndRdx(11), Dct'dW-EndRdx/Rchg(11), Dct'dW-Heal/Rchg(13), Dct'dW-Heal/EndRdx/Rchg(13)
Level 4: Howl -- Posi-Acc/Dmg(A), Posi-Dmg/EndRdx(15), Posi-Dmg/Rchg(15), Posi-Acc/Dmg/EndRdx(17), Posi-Dam%(17), RechRdx-I(19)
Level 6: Scream -- Decim-Acc/Dmg/Rchg(A), Decim-Acc/Dmg(19), Decim-Dmg/EndRdx(21), Decim-Dmg/Rchg(21), Decim-Acc/EndRdx/Rchg(23)
Level 8: Clear Mind -- RechRdx-I(A)
Level 10: Resurrect -- RechRdx-I(A)
Level 12: Fortitude -- GftotA-Def/EndRdx/Rchg(A), GftotA-Def/Rchg(23), S'dpty-Def/Rchg(25), S'dpty-Def/EndRdx/Rchg(25), RedFtn-Def/EndRdx/Rchg(27), Krma-ResKB(27)
Level 14: Recall Friend -- RechRdx-I(A)
Level 16: Teleport -- Jnt-Rng(A), Jnt-EndRdx(29), Jnt-EndRdx/Rng(29)
Level 18: Recovery Aura -- RechRdx-I(A), RechRdx-I(31), RechRdx-I(31), EndRdx-I(48)
Level 20: Hasten -- RechRdx-I(A), RechRdx-I(31), RechRdx-I(33)
Level 22: Assault -- EndRdx-I(A)
Level 24: Tactics -- GSFC-ToHit(A), GSFC-ToHit/EndRdx(33), GSFC-ToHit/Rchg(33)
Level 26: Regeneration Aura -- Dct'dW-Heal/EndRdx/Rchg(A), Dct'dW-Rchg(34), Dct'dW-Heal/Rchg(34), Dct'dW-EndRdx/Rchg(34), Dct'dW-Heal(36)
Level 28: Vengeance -- S'dpty-Def/Rchg(A), RedFtn-Def/Rchg(36), LkGmblr-Def/Rchg(36)
Level 30: Siren's Song -- FtnHyp-Sleep(A), FtnHyp-Sleep/Rchg(37), FtnHyp-Acc/Sleep/Rchg(37), FtnHyp-Acc/Rchg(37), FtnHyp-Sleep/EndRdx(39)
Level 32: Adrenalin Boost -- H'zdH-Heal(A), H'zdH-Heal/Rchg(39), Efficacy-EndMod/Rchg(39), P'Shift-EndMod/Rchg(40), Dct'dW-Heal/Rchg(40)
Level 35: Screech -- Stpfy-Acc/Rchg(A), Stpfy-EndRdx/Stun(40), Stpfy-Acc/EndRdx(42), Stpfy-Stun/Rng(42), Stpfy-Acc/Stun/Rchg(42)
Level 38: Dreadful Wail -- Oblit-Acc/Dmg/EndRdx/Rchg(A), Oblit-Acc/Dmg/Rchg(43), Oblit-Dmg/Rchg(45), Oblit-Acc/Rchg(46), Oblit-Dmg(46)
Level 41: Power Build Up -- AdjTgt-Rchg(A), AdjTgt-EndRdx/Rchg(43), AdjTgt-ToHit/Rchg(43), AdjTgt-ToHit/EndRdx/Rchg(46), AdjTgt-ToHit/EndRdx(48)
Level 44: Conserve Power -- RechRdx-I(A), RechRdx-I(45), RechRdx-I(45)
Level 47: Amplify -- RechRdx-I(A), RechRdx-I(48)
Level 49: Force of Nature -- TtmC'tng-ResDam/Rchg(A), RctvArm-ResDam/Rchg(50), Aegis-ResDam/Rchg(50), ImpArm-ResDam/Rchg(50)
------------
Level 1: Brawl -- Empty(A)
Level 1: Sprint -- Empty(A)
Level 2: Rest -- Empty(A)
Level 1: Vigilance
------------
Set Bonus Totals:
- 5% DamageBuff(Smashing)
- 5% DamageBuff(Lethal)
- 5% DamageBuff(Fire)
- 5% DamageBuff(Cold)
- 5% DamageBuff(Energy)
- 5% DamageBuff(Negative)
- 5% DamageBuff(Toxic)
- 5% DamageBuff(Psionic)
- 4.5% Max End
- 3% Enhancement(Stun)
- 60% Enhancement(RechargeTime)
- 42% Enhancement(Accuracy)
- 12% Enhancement(Heal)
- 5% FlySpeed
- 68.7 HP (6.75%) HitPoints
- 5% JumpHeight
- 5% JumpSpeed
- Knockback (Mag -4)
- Knockup (Mag -4)
- MezResist(Immobilize) 5.5%
- MezResist(Stun) 2.2%
- MezResist(Terrorized) 6.6%
- 12.5% (0.21 End/sec) Recovery
- 8% (0.34 HP/sec) Regeneration
- 7.88% Resistance(Fire)
- 7.88% Resistance(Cold)
- 1.26% Resistance(Energy)
- 1.26% Resistance(Negative)
- 5% RunSpeed
If you do drop the rez I would likely suggest either maneuvers or shockwave in its place. I don't run out of end easily on this staminaless build. Even pre-AB, alternating RA's will be plenty to keep you guys floating on an end surplus. I definitely wouldn't worry about the fitness pool. The only exception there is hurdle if you are going the SJ route, as it makes both CJ and SJ significantly faster. Swift not so much. Vengeance may not be super important, but it's low-hanging fruit when you already have two leadership powers, and if you have veng+rez, there's no stopping you at all even if you screw up badly.
Thanks guys. Even though it's really early, I'm going to respec so I can get out of the Fitness pool. The build is tight enough to waste a power on that if I really don't need it. I made a build for myself (doesn't have the IOs yet) using both of your builds to help me out. Thanks a lot!
Virtue
Heroes
50- Fire Kinnnnn (Fire/Kin Controller)
50- Shielded Deity (Elec/Shield Scrapper)
50- Doomaster (Invuln/Fire Tanker)
Villains
50- Farm (SS/SD Brute)
I'd get in touch w/ DRMIKE2000 who runs an offensive Emp duo for guidance in emp primary....
Theres also a Sonic Attack Chain thread being contributed to, working on updating the OP...
Do I hear my ears burning? 
I'm dont think there's anything special I can add to this, its hard to go wrong with an Empathy duo to be honest.
I had Healing Aura and Heal Other and Rez. I didn't have Hasten, which is a mistake. I had Hover and Flight and Recall Friend (because I was new to dual boxing, and it helped to be able to summon my other half when they got stuck on a cave wall). And I ran Assault and Manouvers. I drew the line at Tactics because I was getting the benefits from mutual Fortitude and Clear Mind.
Thunderstrike sets in my attacks, Red Fortune in Fortitude and that was about it for sets. Its been a while since I played them...
One point to clarify, BalleRyan. I use dual-boxing to refer to one player controlling two characters using keystroke broadcasting software, you're talking about playing with a friend. Dual-boxing my way generally means that you play each character a bit worse than you would if you weren't trying to split your attention, but in the case of a mutual buffing its actually a big advantage. No need to communicate or cooordinate, just press the button and both characters will use Fortitude or AB or whatever on each other.
I also alternated auras e.g. O-Man would have Regen and Recovery in slots 7 and 8, O-Woman would have Recovery and Regen in slots 7 and 8, ie the other way round. This way, either key press (7 or 8) would bring up one of each aura, and you could have both of them effectively permanent.
Hi,
My friend and I both made Empathy/Sonic Attack defenders to dual box together. So far, we have gotten to level 9. Here's what we have so far:
1: Healing Aura
1: Shriek
2: Scream
4: Howl
6: Swift
8: Combat Jumping
We're not planning on picking up Heal Other, Absorb Pain, or Resurrect. I read that for dual-boxing these characters, the only heal you need is Healing Aura because you'll have two people using it.
I'm looking for a build that goes along with what we have so far. We're looking for Super Jump in the high 20s because we'll be getting a raptor pack.
Any help would be greatly appreciated!
Virtue
Heroes
50- Fire Kinnnnn (Fire/Kin Controller)
50- Shielded Deity (Elec/Shield Scrapper)
50- Doomaster (Invuln/Fire Tanker)
Villains
50- Farm (SS/SD Brute)