To be fair to Larian, I’m not sure you’re supposed to like him necessarily. I can imagine his story is supposed to be sort of tragic but all I feel is that he’s tragically written.
I never really found the ‘lost powers’ story arc particularly interesting or believable. Does it imply that removing the tadpoles instantly reverts said companions to their previous levels of expertise? Or are the tadpole effects permanent so the companions have something like amnesia with regard to their prior knowledge? It’s just a narrative muddle. Perhaps Larian will resolve it but personally I just don’t really care for it.
As you said, with Wyll there is an obvious conflict with his supposed notoriety and his palpable weakness in combat. He comes across as a compulsive liar and there’s no way I’d hang around with someone like that, in reality or fantasy.