I personally did not see much evidence for the idea that Khan simply "chose" to brawl. I saw Khan trying to stay on the outside for most of the fight and Maidana not letting him stay there. You do not simply decide to let a guy unload 3 or 4 uppercuts on you repeatedly; I saw Maidana imposing his will in later rounds, not Khan allowing him to do so. I believe that in a Bradley fight, Tim would also get there without having to eat as many punches as Maidana did.
I dunno man, I think Maidana is way better at cutting of the ring than Bradley. Bradley also lacks the power (that Maidana had) to trouble Khan, and when Khan is comfortable and gets into a groove, he's almost impossible to outbox.