I feel like with many of the other companions and story arcs it tapers of a bit in the third act. I failed to save Duke Ravengard and it felt like that had much too little impact on Wyll.
I wanted the chance to hand over the role of saviour of Baldur´s Gate in the end battle to him and let him do the speeches and stuff. My character not being the classic hero that people would rally around, it would have made sense for them to put him at center stage and let him be the front figure.
Things like that would have given me more of the Wyllfillment I got from him in the early game. But he's still a great and somewhat underrated character (and he's the cutest and my favourite of all the male romance options).