I have never really noticed the "grip angle" of any pistol I have ever shot, I think the people who make it an "issue" are mostly people who have used the same platform for decades and just have a hard time adapting at this point to anything even remotely different.
FWIW, I think the hump on the subcompact Glocks is perfect, the grip is fairly large and does make you hold it a specific way, but once I just went with it and stopped screwing around with magazine extensions the gun started shooting better with me than any other pistol I own. The 23, not as much, still have some ground to cover before I'm anywhere as good with it as the 27.
I think any amount of practice will quickly render grip angle insignificant.