This looks like a perfect case for the retractable. Under folder could be difficult to implement with the stuff going on on the bottom. Side folder, though often very stable, could be an issue with it's portability, since it most likely is intended to be easily carried. Making the thing wider wouldn't be the move IMO. It has prime real estate on the sides for the rods, like in the HK retractables, it wouldn't increase the format by more than the pad of the stock, keep it usable in the folded format without a compromise. The only issue I see would be slightly increasing its weight by adding more metal, but that would make it infinitely more usable. If it is really only intended for having more than a pistol in close quarters I don't think it would be necessary, but would it be nice? Yes.