Yes..... Personally, we did have a few PM's about Const's personality after my short-lived FanFic, and it was basically inevitable that Const would "head to the dark side" due to the weight of things collapsing on him. Mental illness, anger, steamed up emotion from being everyone's whipping boy and known only as a "snitch" to everyone (Probably including Tony....) Tiffany's death is the perfect excuse for Const to unleash all of his anger from the past on anyone who he pleases, (perhaps Tony, as well?....) Much similar to the Joker that Jack Nicholson portrayed. A low-level thug who, when fell into a vat of chemicals and became "mad", it was his perfect excuse to be everything he always fantasized about.
Although, of course, you wouldn't want const turning into a major villain which then results in 20 chapters more. Perhaps he just has a few intense conversations with Tony and pretty much becomes a nuisance to everyone. Perhaps even a fight or two?
idk though, I'm interested to see how you will pan this out. This just my opinion, however.