Makes you wonder sometimes. Why try and reinvent the wheel. We have M2, M3s, Stikers, LAVs, can't you more or less do all of this with a modernized M113?
Certainly a remote Turret with an Auto Cannon is possible, Missile Launchers have already been added. It is already amphibious, there are ATC, MHQ, and Ambulance versions. Finally anything with enough Armor to stop a tank round or missile, will be a tank, and not an IFV or Battle Taxi, it won't be air mobile, and it won't be fast anymore.