EDIT: Note to self; Don't post at 1 AM if suffering sleep deprivation
I really, really doubt you'll need the end reductions in the heals, especially with Stamina. Three recharge/three heal will do you a lot better. The heals are noticeably weaker than Empath heals, as you'd expect, and you want them up as much as possible in rough situations. My Rad/Thermal uses her heals AND attacks all the time, and I very rarely have endurance problems on her, with three recharges in the heals.
I don't think I'll be slotting any heals in Power of the Phoenix. Sure, it doesn't take the person to full health, but throwing a quick heal on them after using it will. Is it really worth two slots on a situational power when you can just use one of your other powers to fix the issue?
I don't have the final two powers from Thermal yet, but I generally find three accuracies to be overkill. Especially when removing one or two would let you put recharges in Melt Armour. Either way though, they look well-worth six slotting, and you can always try things out once you have one and see what works best. 
I had 1 end reduction in each heal but I will probably take them out, like Cybercel I have plenty of end even in long fights and I do plenty of fighting.
I have every /thermal power bar Melt armour (8 1/2 bars to go
) and I highly recommend tham all.
Heat Exhaustion is a current favourite, 2 recharges make it ready for every fight or multiple times for very hard bosses/GMs, also seems to have a nice accuracy, hitting orange bosses with 1 accuracy regularly and mostly hitting purples. probably put another in so it hits when you really need it to.
Forge recharges pretty quick, I have 2xtohit buffs and I can keep it perma on 2 people (I might have a recharge but I cant actually remember right now).
I am not an enormous invis fan and would probably prefer to take tactics/assault myself, another thing to consider is keeping yourself alive and upright, my empath took acrobatics from the leaping pool and it works wonders, even kept me on my feet against Hami blasts (only non tank standing 
)
I've recently hit level 50 on my Empathy/Radiation Blast Defender, and is now trying to make a healer/buffer on CoV.
I've spent around an hour perfecting this build so I would like to hear your oppinion.
Keep in mind that this build is for teamplaying ONLY, which means no attacks exept the ones you start with.
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Exported from Ver: 1.7.6.0 of the CoH_CoV Character Builder
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Name: Dark Incendo
Level: 41
Archetype: Corruptor
Primary: Dark Blast
Secondary: Thermal Radiation
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01) --> Gloom==> Acc(1)
01) --> Warmth==> EndRdx(1)Rechg(3)Heal(3)Heal(7)Heal(9)Rechg(11)
02) --> Fire Shield==> DmgRes(2)DmgRes(15)DmgRes(23)
04) --> Cauterize==> EndRdx(4)Rechg(5)Heal(5)Heal(7)Heal(9)Rechg(11)
06) --> Hurdle==> Jump(6)Jump(33)Jump(33)
08) --> Recall Friend==> Rechg(8)
10) --> Plasma Shield==> DmgRes(10)DmgRes(15)DmgRes(23)
12) --> Hasten==> Rechg(12)Rechg(13)Rechg(13)
14) --> Super Speed==> EndRdx(14)
16) --> Power of the Phoenix==> EndRdx(16)EndMod(17)Heal(17)EndMod(19)Heal(19)EndRdx(25)
18) --> Health==> Heal(18)Heal(34)Heal(37)
20) --> Stamina==> EndMod(20)EndMod(21)EndMod(21)
22) --> Thaw==> Rechg(22)
24) --> Stealth==> EndRdx(24)EndRdx(25)EndRdx(40)
26) --> Grant Invisibility==> EndRdx(26)EndRdx(27)EndRdx(27)
28) --> Forge==> Rechg(28)Rechg(29)Rechg(29)
30) --> Teleport==> EndRdx(30)EndRdx(31)Range(31)Range(31)Range(33)
32) --> Blackstar==> Acc(32)Acc(34)Acc(34)
35) --> Heat Exhaustion==> Acc(35)Acc(36)Rechg(36)Rechg(36)Acc(37)Rechg(37)
38) --> Melt Armor==> Acc(38)Acc(39)DefDeBuf(39)DefDeBuf(39)Acc(40)DefDeBuf(40)
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01) --> Sprint==> Jump(1)
01) --> Brawl==> Dmg(1)
01) --> Scourge==> Empty(1)
02) --> Rest==> Rechg(2)
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