Why not go with a .223 caliber AK-74 and scope it? Get one with a folding stock, tactical scope on it and test it out. See what it can do for you and play with it. If you do this, give us some feedback.
Some indoor ranges allow the use of .223 rifles, so perhaps you can get more range time with that vs. a .308 rifle.
This guy's humble opinion is an AR. Plenty of good manufacturers, plenty of good parts available, completely customizable. You can either buy or build an upper for any and every purpose you see fit.