Fel Flame isn't that bad compared to MG as well, as long as you extend both your DoTs. I don't agree that KjC is a "horrid design". If it wasn't a passive but had some kind of charge systems (say you could cast 1 spell per stack on the move gaining 1 stack every 20 seconds with a maximum of 3 stacks) it could have a lower penalty (maybe even none at all). I think that with such a charge system it would still be useful but not overpowered to the point of being the only option.
I do think (and I have been saying this since the very start of the beta) that AV is a crappy design, you get rewarded for standing in the bad. And it is hard to balance. AV should be completely reworked into something that can rival KjC.