Considering blockland is blocks I try to stay in the blocky theme..
There's this great shape called an octagon, it could be used to your advantage.
As for the other stuff, the ejection port is too small, as on the real gun it goes further up the slide, almost to the middle.
The grip looks too thick, and uncomfortable to hold as a result
Lastly, the trigger guard and parts of the frame surrounding it look less round than on the original gun. The 1911 trigger guard is in a shape almost of a circle, partly stretched in the middle. Both sides are semicircles. Yours, however, consists of 1 almost semicircle and one almost quarter circle, with a 70-80 degree angle thrown in.