After i was finished, my biggest thing was, i actually wanted to lead and carry out my roles when joining my supposed faction, for instance, when you join the institute and become the director, i would much rather that happen earlier, and i spend time actually shaping the commonwealth in whatever image i have the new institute direction, same goes with the brotherhood or the other 2 factions.
I hate that, by the time you hit the top in every faction, the game is done, that seems to be the trend in all of these games, you never get to experience the result of your choices in full, and i really wish i could do it in this game.