Base Idea: Mobile
 

This is an idea I've been working out in my head. The southern base could be a large aerial craft. Every so often, the base entrances would lock and the flying base would ascend to heights that would hide it graphically. Then, after a little while it could set down in another location on south ridge island. So, it could be like 2 bases in one. Maybe make it a futuristic oversized airship to match the Lexel rifle technology.

'Al-Capone Era'

It's funny, I don't remember the Lexel rifle or the BAR being Capones weapon of choice...

Check and Mate

M1A1 ftw.