[Vapor]

I'm not too into Daredevil comics (although another film would be cool) so I'm just curious but what about Purple Man? He could use his powers to control someone such as Gladiator so there is a physical threat but Purple Man would be the main, fleshed out villain, perhaps using his powers to try gain a position of power within the city.

Or, perhaps unlikely but seeing as Daredevil is back with Marvel could they not (have Kingpin working from the background as suggested) use someone elses villain, maybe someone like Taskmaster? Someone who might not get featured in the other more 'super power based films' but would be cool to see on screen nonetheless... He seems like he'd be a good fit for the more gritty/street level film Daredevil would likely be.