I see no reason a law abiding citizen should not be able to own any firearm they choose as long as they have the means and the knowledge to use it.
I would suggest instead of creating new laws preventing the sale and distribution of semi automatic firearms and magazine limitations, that congress enact a new class/ category system similar to our auto licensing system. In order to drive a specific style of car/truck/motorcycle each person must obtain the appropriate class of license or permit.
Longrifle (Shotguns, rifles, and other general firearms used in hunting) All people with state of federal hunting licenses with carry over for this permit.
Sidearm (pistols and other lightweight single hand firearms)
Recreational (semiauto rifle and firearms not recognized in Sidearm permit