Funnily enough, amongst my many gripes about her, Venat's being a revered genius never actually bothered me that much. As you say, given that someone who has previously occupied the seat of Azem likely contributed tremendously to her community, the fact that Convocation members tend towards the remarkable anyway, and that she has lived an unusually long life, I think that part of her characterisation was perfectly plausible.
What does bother me is how they never touch on that information after that point. Lahabrea in JP is referred to as "old man" when he hasn't yet retired; how much older then, is Venat, and why is she never presented as anything other than intelligent and experienced whilst retaining a relative sense of youth in comparison? Why does no one remark on how odd it is that she refuses to return to the star, and the potential reasons behind it? Or that her innate genius may have led to a form of arrogance resulting in such terrible decisions?
There is plenty there to make Venat a more fleshed out and ambiguous character, and yet they do nothing with it, which I take more issue with than her being "too" gifted.
What I've already been saying. Develop a stronger mentality to deal with disagreements and stop taking them personally, or go somewhere that will not cause you distress. If the game itself is bothering you - which I understand to some degree, it's not easy to see something you love change, especially when it feels for the worse - then you can either continue to play and hope for the best, or find a new game. Making yourself out to be a victim isn't the answer, though, and you may actually find some comfort in the realisation you are just one opinion amongst many.
You were rather adamant about the SMN changes staying as well despite the outcry, as I seem to recall.there is a group of people who do not want players like me around and are cheering this whole thing on.