I'd be disappointed in a RB taken in the first four rounds - Ridley & Vereen have large roles to play, a veteran (Blount or MJD) will arrive and Bolden is serviceable.
Next year, absolutely. It's pretty much a given that a rookie RB can contribute more quickly than can a rookie WR, given the amount of knowledge/familiarity with the offense each position requires.
Of course, if they can somehow trade Ridley for a 4th round pick, I'd be cool with using that on someone who doesn't scare the shit out me every time he touches the ball. (yes, overreaction, yes, he's not that bad, yes, I'm trying to forestall the "but ridley doesn't actually fumble that much!" conversation from happening yet again)