On the other side of that Graves isn't nearly skilled or talented enough to play that way in the NHL consistently, if he's to stick in the NHL he has to adapt. (I'd argue he just doesn't have a long-term NHL future)
I don't think you're wrong there, but if you're going to use him (albeit sparingly) you should go for broke. Trying to get him to play more "balanced" just takes away what makes him good. There are just some guys who just flat-out should never, ever be trying to block shots. Graves is one of them.