Badder-ass?
Who would have the most potential to the new big badass in these scenarios?
1) Colossus - keeps the Cyttorak and stops having Bob Ross moments, gives into his anger and doesn't stop to freak out every time the demon comes out. He leaves the "X-whatever" team he is on and takes Kitty with him to wherever the road takes them. Side note: she regularly withholds sex from him to get her way.
2) Batman - gets over the "no firearms" schtick and spends some Bruce Wayne money on an arsenal that would make the Punisher crap his pants. He stops having any pity for the Joker and similar villains and some heroes as well.
3) Thing - gets Reed to create a device to hasten his aging process, causing him to immediately age 500 years in a matter of days. This evolves him further, multiplying his strength to a great degree. He then trains at the X-men's danger room and learns martial arts to go along with his good ol' brawling techniques.
4) Hal Jordan - absorbs the Green Lantern light, such as he did when he first became Parrallax. He also goes and absorbs the Blue Light, creating a balance within himself. He realizes a new sense of purpose and goes out to fight greater evils such as he wanted to do as the Spectre, but wasn't in control.
5) Thor - his balls drop and he begins to find girls interesting.