Get a G34 slide, and either a strike industries comp, or a threaded barrel and a compensator/brake
If you're in a commie state that bans threaded barrels then get the strike industries comp because it's no threaded barrel required and looks like some GiTS Shit, especially with a WML.
Also, get a Ghost disconnector. That's not a ghost gun joke, it's a real company and they make pretty good drop in trigger shit