I rode dirt bikes all my life, and am pretty good on one! and bought a Monster 796 as my first street bike. Put 9000 km on it the first year with no problems and didn't come close to laying it down, moving or not. I'm a short guy too (5'8") and found the Monster to be a great first bike.
I also rode the Shiver but preferred the Monster. It's a really tame, smooth riding bike and if you're not going to ride it for more than a few hours at a time, I think you should at least consider one if you've been thinking of the Aprilia.
Good luck, and ride safe.