Simple idea really, if you have a mini gun you shouldn't be able to holster it. I mean they are just so huge, unless they could make an animation where it attached to the ammo pack on your back but.. idk this is why I don't use big guns.
Which would be the point. Throw it over the shoulder and latch it on to the ammo pack. More or less the same animation you'd see with Hammers/Claymores in Oblivion. (Except the Minigun latches on to the side of the ammo pack, and not across the back.
I agree, I don't like using Big guns in general cause they look so huge and awkward, but they do kinda look well enough if you're strutting around in power armors. Honestly, I'd rather see a Lower-back (Belt line approximately) Ammo coil for things like Miniguns instead of the huge cumbersome backpack, and have the gun itself thrown over across the back. One thing I never did really understand is having to RELOAD the minigun. but either solution, nothing breaks immersion like a meter long deathpipe just goin *poof* out of nowhere. (I know it sounds stupid, but that is one of my biggest peeves in Morrowind too, is the lack of any holstered weapons, and even a decent mod that allows such.)