Well let's see... aside from making blood constructs/distance attacks with the drops and puddles and such, you also want heightened physical attributes as well as the ability to decrease them in others as well as being able to control somebody's body by using their blood? And to sustain power he has to drink blood? Honestly if he was a vampire it'd make more sense, but as is it seems a bit over powered. And really, you take all the blood in a person's body and freeze it solid what would you have? Maaaaybe a few water balloons full.... that's not much to work with even draining you dry.The whole being able to jump into a villain's body and control them is a bit of a downer too.

There's just so much more out there you could work with. Hydrokinesis has always been one of my favorite underused powers. I'd say terrakinetic but there's already somebody in talks to either have that power or just skin and bones made of earth and stone. Hell give him the ability to control a mystical red flame and make fire constructs. 

~KL~