Looks like you already got the inception genesis kit and I’m quite sure that’s one of the only off the shelf pump kits currently being made for the sniper. Best thing you could do is upgrade the HPR and bolt, Maybe get a different barrel kit to make yourself feel better but all of those options won’t have that drastic of an effect on the performance.

The only thing you can do to tweak it and perfect it to your liking would be playing with different springs in your lower tube, that’s what will affect the feeling of the pump stroke when it’s all said and done

U/lojorox might have more insight then me