Please might i ask to update its post adding a version without that foregrip? I never stood those on firearms >. < 
I’m not going to claim that rail-mounted perpendicular grips aren’t butt-ugly, but foregrip in general is a feature that’s not going away. See for example
here.
Handling recoil.
Placing the hand further from parts that heat up.
Also, having a proper foregrip discourages the user from instinctively trying to use
magazine as a grip (depends on placement of the magazine, of course).
It provides an added lever of control and they really help with rapid target acquisition. To the point that they are considered an assault weapon feature.
…“are considered” by whom?
Surely it’s not an effect of faceless and omnipresent gravity. I have seen mockery of the term «assault weapon» as such from “gun nut” crowd, for that matter, and inclined to agree that it’s an anti-concept, given lack of straightforward definitions.
My opinion is an angled grip like a tommygun or maybe 45 degrees, butted up against the magwell, would likely be ideal.
But if the grip is too close, wouldn’t arm sometimes push against the magazine?
Including lever action rifles, which should have a 4-6 tube carousel of ammunition able to hold 20+ rounds (check out the SRM-1216 for reference, then put it on a lever action rifle).
An interesting design.
But where it’s useful? Selectable magazines are desirable
for shotguns (like side-by-side tubes of NeoStead 2000, though of course detachable is better), because there’s almost always more than one type of ammunition that can be useful. Even a hunter who only wants ducks may keep some slugs at hand, because close encounters of a nasty kind with boars happen.
While for rifles variety of rounds does exist, actually carrying several types seems unusual. I don’t see a solid niche for multi-magazine rifles unless quickly swapping variant ammunition somehow becomes a major consideration too (
not that it’s implausible, but non-trivial).
Specifically for lever action, isn’t simplicity its advantage? When extra mechanisms make strong sides of the basic design meaningless, we are looking at Mateba Autorevolver tier of incongruous complexity. What’s the point, other than as a novelty?
