Just as a notation thing, Flaming Bash should have Extra Condition.
While it isn't technically stated I would imagine that the free Charged that comes with Burst Area is keyed to Burst Area; I don't think you can kinda repurpose it to boost Unavoidable instead.
Also, a couple points worth noting for Nerves of Thorn - first, my standard rules for Reaction powers are that they are either Sustained (and you can choose to turn the whole thing on or off on your turn, but it turns off if you get Stunned) or Permanent. I think Permanent would make more sense in this case? Second, if you have it active alongside Ember Burst, it will allow you to react to attacks at range, which feels like it might not fit thematically.
Lastly, the power description saying he perceives any contact as an attack would suggest that it ought to trigger when an ally touches him, but currently that isn't the case. As with the range thing that might be intended but is probably worth noting.