Do what you want
Hey bud, if you want to get better at shooting FIRST(HIGHLY recommended), there are lots of guns better equipped to help you do that than a Ruger LCR. The LCR is designed pretty much as a carry-only platform - no hammer, groove rear sight, light weight, slim profile. It's not intended to be a gun you practice with, at least not much. MY fear is that you buy the gun, wind up not being able to hit what you want to at the range to your satisfaction and wind up blaming the gun and/or thinking you're not a good enough shot to be trusted to carry it for defense.
I'd say get a 6" barreled 22LR, either semi-auto or revolver, get some training and go shoot it. Paper, pop cans, whatever you like and can have fun with.
THEN work your way up to something else you can handle. The LCR in .357 Magnum - if you still like them at that point - is a peach!