The more I read this thread, the more I want a handgun that looks like a Mauser C96 (AKA Broomhandle), is simpler / more modern in design, takes M1 Carbine mags and fires M1 Carbine rounds. With a really effective flash hider on the end of the barrel.
Now that I think of it, it's going to look like the Han Solo's blaster, especially if you mount optics on it.