I believe the slim frames models are what you would be looking for. But they dont offer a compact size 45, you would have to go with the full size(21) or subcompact(30).
I know Glock calls the G30 a sub-compact, but in my opinion it's more like a compact in physical size. G30, G30s, G30sf, or G36 are your only options at this time.
Doubt it. Some state police agencies have adopted it along with some bigger departments. Pennsylvania SP is one agency using them. The troopers seemed to like them when I talked to them... slimmer frame than the .45 acp and I guess the round did better in glass and metal penetration tests. You can also get a mid size .45 GAP model