The original KRISS Vector concept was for a submachine gun meant for specialized MIL/LE use — designed with the goal of allowing the user to better stay on target in full-auto mode, as compared to existing submachine guns in that role like the HK MP5.
Everything that people seem to dislike aesthetically is there for a functional reason on the original gun — to reduce recoil and muzzle rise — for example, the bore axis is directly in line with the strong hand, and the recess behind the magwell reduces recoil by housing an inertia block that articulates with the bolt — so instead of the blowback pushing the bolt into a buffer tube, it curves it in an arc slightly downward into the recess, pulled by the inertia block.
Those design elements were meant for full-auto mode — they become less important (although still useful) with the semi-auto, and even less so (or meaningless) with this rimfire — which abandons the inertia block altogether.
So it’s understandable that folks looking at this strictly as a .22lr would dismiss the design as having what the car guys refer to as “boy racer” looks. But at least it’s descended from a well-regarded “form follows function” submachine gun.
Here’s what’s going on in that space behind the magwell: