I've made the same switch
My first bike as a 2001 ZX-6R, which is nearly identical to the ZZR600 of today. I now have a GSXR750. Like you, I'm short. The good news is, the GSXR600 & 750 have are virtually indistinguishable without their badging (there are about 3 little giveaways). The cockpit of each is the same, so if you fit on the 600, you'll fit on the 750. I studied them both in detail when I worked at a bike dealership.
The larger problem, and the one I still struggle with, is the suspension. Stock the GSXR comes set up for "average" male, with "average" riding conditions. I'm a girl, 5'4", 125 lbs, and love to get deep into the corners. That's a far cry from 5'10", 180 lbs guy, who stays mostly upright.
Without the money for a full suspension swap, it's been a struggle to find settings that work well for me. My goal is to test & tune my bike at the local track... they have a "test & tune" on Wednesday nights (20 minute session, 3 times, for $60). You might do well to talk to you local shop and figure out a good way to dial in your suspension and perhaps find a similar track deal in your area. There are also a lot of good (and bad) resources on the web.