We don't want the game to be packed 100% to the brim with action sequences, (cough cough, ANF, cough cough) we want mystery. Bigby's a professional investigator.. take advantage of that.
Bigby isn't JUST a badass. Sorry for bringing TWD into this again, but if you have played season 3 you'll know why I'm saying this. They Daryl Dixon'd Clementine's character and only added her into the story so we could see what an awesome badass she had become. Don't do this with Bigby.
There are SO many characters in the comic book and they're all really cool. If you're going to add one in, don't forget about them midway into the story. If a character doesn't have any significance to the storyline, or is in the game JUST to be in the game, don't even bother adding them in. It's pretty annoying otherwise.
The game doesn't have to have multiple endings for it to be good. Y'know what they say kids, "It's the journey that matters, not the destination."
Feel free to add anything else in the comments.