No comments? Either my build is pretty good, or it's beyond fixing lol
It looks a very functional and fun build 
The only thing I can think to comment on is replacing "Swift" with "Hurdle", as you have "Superspeed" Hurdle will be of much more service (even with Superjump, I much prefer Hurdle in combat to jump *over* enemies if stuck in a big mob, and with Rad/ this is quite likely to happen.)
Defiant EU
Quaver: Kinetics/Sonic Defender
Semiquaver: Sonic/Kinetics Corruptor
Agreed, you're off to a solid start. I only see two minor slotting changes I'd recommend.
The first would be to add a little range enhancement to Psychic Scream, to improve its coverage. Not super important when soloing, but when teaming, it's nice to consistently get your ten targets' worth. I like a ton of range enhancements on my Psychic Scream, but for starters, Positron's Blast: Damage/Range takes Psychic Scream from a 60' cone to a 70' cone, that might be enough for you.
The second would be to add slow enhancement to Lingering Radiation, to floor enemy movement. The AI will panic and run away if it's unable to attack for ten straight seconds, and because you have so many stackable recharge debuffs, you'll find that will happen a lot. Slow slotted LR keeps them from getting anywhere. I realize you're tight on slots, but I think swapping out two or three of your common IO's for Acc/Slow and Slow/Rech/End "1,000 inf wonders" from cheap slow sets might be all you need, no additional slots needed.
Keep an open mind for other changes if you find they suit your playstyle. For instance, you may find you don't need Stamina or Conserve Power, even when soloing or otherwise vigilance-starved. You may find you prefer ED capping the recharge enhancements in AM, trading the 5% global recharge set bonus for 8 seconds less AM downtime (which partially offsets the global recharge bonus loss). You may find at level 44 and above, when you're groping for throwaway 1-slot powers, that both Swift and Hurdle might be something you'd like, or maybe another +def pool power to mule another LotG. You may find yourself on teams that let you use Fallout+Mutation a lot more than you expected, or you may find yourself on teams that never let you use Fallout+Mutation at all, be prepared to fine-tune those two powers to your teaming needs.
You bring up some good points that I didn't really think about. You're definitely right about the slow in LR. I'll probably remove the Lady Gray Proc from RI since it doesn't seem to fire much at all and throw it on LR.
Back when I got this game, one of the first toons I rolled was a Radiation/Psychic Defender. He was a blast leveling and a force to be reckoned with solo. Then I got into PvP and did that for awhile. Annnnd towards the end he was used mostly for Katies. Anyway, it's been a long time and he still has white SOs.
Here's a build I put together with focus on recharge and and some damage. Should I find a way to fit more slots into Fallout? I read on another thread that Conserve Power really isn't needed, but after using my toon so much, he loses end even with AM up. This could be due to white SOs, though. Should I bother with procs in RI, Choking and Psi Tornado?
I plan to use him for solo/teaming pve. He's also 50, so this is a respec build. Let me know what you guys think! =)
Hero Plan by Mids' Hero Designer 1.401
http://www.cohplanner.com/
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Level 50 Mutation Defender
Primary Power Set: Radiation Emission
Secondary Power Set: Psychic Blast
Power Pool: Speed
Power Pool: Leaping
Power Pool: Fitness
Power Pool: Leadership
Ancillary Pool: Power Mastery
Hero Profile:
Level 1: Radiant Aura -- Dct'dW-Heal/EndRdx(A), Dct'dW-EndRdx/Rchg(3), Dct'dW-Heal/Rchg(3), Dct'dW-Heal/EndRdx/Rchg(5), Dct'dW-Heal(5)
Level 1: Mental Blast -- Decim-Acc/Dmg(A), Decim-Dmg/EndRdx(7), Decim-Dmg/Rchg(9), Decim-Acc/EndRdx/Rchg(9), Decim-Acc/Dmg/Rchg(11)
Level 2: Accelerate Metabolism -- Efficacy-EndMod(A), Efficacy-EndMod/Rchg(11), Efficacy-EndMod/Acc/Rchg(13), Efficacy-Acc/Rchg(13), Efficacy-EndMod/Acc(15), Efficacy-EndMod/EndRdx(15)
Level 4: Radiation Infection -- DarkWD-ToHitDeb/Rchg(A), DarkWD-ToHitdeb/Rchg/EndRdx(7), DarkWD-Rchg/EndRdx(17), DarkWD-ToHitDeb/EndRdx(17), Achilles-ResDeb%(19), LdyGrey-%Dam(19)
Level 6: Hasten -- RechRdx-I(A), RechRdx-I(21), RechRdx-I(23)
Level 8: Combat Jumping -- LkGmblr-Rchg+(A)
Level 10: Psychic Scream -- Posi-Acc/Dmg(A), Posi-Dmg/EndRdx(21), Posi-Dmg/Rchg(23), Posi-Acc/Dmg/EndRdx(25), Posi-Dam%(25), RechRdx-I(27)
Level 12: Enervating Field -- EndRdx-I(A), EndRdx-I(29)
Level 14: Super Jump -- Zephyr-Travel(A), Zephyr-ResKB(33)
Level 16: Swift -- Run-I(A)
Level 18: Lingering Radiation -- RechRdx-I(A), RechRdx-I(29), RechRdx-I(31), Acc-I(31), Acc-I(31)
Level 20: Health -- Mrcl-Rcvry+(A), Numna-Regen/Rcvry+(50)
Level 22: Stamina -- P'Shift-EndMod(A), P'Shift-EndMod/Rchg(33), P'Shift-EndMod/Acc(33), P'Shift-End%(34)
Level 24: Will Domination -- Decim-Acc/Dmg(A), Decim-Dmg/EndRdx(34), Decim-Dmg/Rchg(34), Decim-Acc/EndRdx/Rchg(36), Decim-Acc/Dmg/Rchg(36), Ruin-Acc/EndRdx/Rchg(36)
Level 26: Telekinetic Blast -- Decim-Acc/Dmg(A), Decim-Dmg/EndRdx(27), Decim-Dmg/Rchg(37), Decim-Acc/EndRdx/Rchg(37), Decim-Acc/Dmg/Rchg(37), Ruin-Acc/Dmg/Rchg(39)
Level 28: Psionic Tornado -- Posi-Acc/Dmg(A), Posi-Dmg/EndRdx(39), Posi-Dmg/Rchg(39), Posi-Acc/Dmg/EndRdx(40), Posi-Dam%(40), FrcFbk-Rechg%(40)
Level 30: Choking Cloud -- BasGaze-Acc/Hold(A), BasGaze-Rchg/Hold(42), BasGaze-EndRdx/Rchg/Hold(42), BasGaze-Acc/EndRdx/Rchg/Hold(42), G'Wdw-EndRdx/Hold(43), Lock-%Hold(43)
Level 32: EM Pulse -- BasGaze-Acc/Hold(A), BasGaze-Acc/Rchg(43), BasGaze-Rchg/Hold(45), BasGaze-EndRdx/Rchg/Hold(45), Lock-Acc/Rchg(45), Lock-Rchg/Hold(46)
Level 35: Assault -- EndRdx-I(A), EndRdx-I(46)
Level 38: Psychic Wail -- Oblit-Dmg(A), Oblit-Acc/Rchg(46), Oblit-Dmg/Rchg(48), Oblit-Acc/Dmg/Rchg(48), Oblit-Acc/Dmg/EndRdx/Rchg(48)
Level 41: Power Build Up -- RechRdx-I(A), RechRdx-I(50), RechRdx-I(50)
Level 44: Fallout -- HO:Nucle(A)
Level 47: Conserve Power -- RechRdx-I(A)
Level 49: Super Speed -- Run-I(A)
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Level 1: Brawl -- Acc-I(A)
Level 1: Sprint -- Clrty-Stlth(A)
Level 2: Rest -- Heal-I(A)
Level 1: Vigilance
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Set Bonus Totals: