Ok honestly, I would recommend whole heartedly against a slurve.
Often a slurve is really the result of a pitcher not being able to throw either a curve or a slider well, so they have a pitch that is kind of in between, which often hangs and usually isn't very sharp.
Now even if you could potentialy have a good slurve. I think it would mess with your other pitches severely. Not that man guys can throw a slider and curveball, and keep them consistent, because they often mix the motion. Adding a midpoint of the two into your repetoire would make it extremely hard to be precise with your different breaking pitches.
Honestly I would learn a changeup above all else. Maybe play with a splitter, if you have a good one, it can be a great pitch to confuse hitters on ocassion.