I wanted the ruger 22 because I like the look, but a 22 would have no stopping power for a Medium pistol.
I was actually thinking, for the rebel heavy pistol to be a sort of Mare's leg sort of thing, or like a sten, cheap looking. I actually don't think the pictures are the most recent ones I made. I'll upload the new ones soon.
The way I see it, the advantage that the .22 would have is its silence. Even 9mm suppressed guns are still pretty loud, but .22s that are suppressed are very quiet.
I think the Stechkin would be a good choice for the rebels' machine pistol, but it's your call, of course.