Your talking about additional variables while the existing aren't worked out in order to make a more balanced combat, because they are enough to try, but the problem is they aren't worked upon. That means overhauls like the ones you are suggesting are very unpractical and not likely to be even considered in reality to be even implemented. No matter how you look at it new variables aren't going be the solution if they won't be applied to some sort of refined, polished structure with the existing mechanics otherwise it will lead to imbalances and more questions marks on top of the solutions that will follow to fix the flaws of your own solutions.
I call it re-inventing a wheel, something works or can work or have something to work with, but players, developers try to present us with similar ideas and features that ultimately have the same goal, but work differently in practice and not intended as always and all that as an excuse for what, variety? But we can create it with what we already have.
This session we had numerous mechanics introduced with low success and that is only because of poor perspective of developing, the existing mechanics aren't used to full potential and thus making it difficult to add new things to a broken system. New stuff is added when the previous existing isn't finished, isn't polished and not even put to use, just toyed around with.
Example of that would be current shotguns, they have been gifted with a known and already existing variable to them - knockdown, but the issue is they fail to balance it properly out to have some sort of positive effect on the current combat system and it just purely rots there without any greater purpose or reason. The same principle can be applied to most weaponry out there and that is one reason why our current combat system lacks variety, the thing is this game already provides enough to work with it and create something interesting, yet you are here and want new mechanics, and what for?
if you can shoot 60 bullets at the same speed a sniper shoots
We don't have weapon speed, because we don't need weapon speed, because these weapons are balanced through other means, you might not dish out so many bullets at the same time, but it is not the reason why it is balanced nor it is the solution for it even if you think it is not, they have different effect on the target, damage etc. etc. have different appliances in practice, currently it is not perfect, but it requires more work with what we have.
So no, your experimental combat system changes are universally flawed and unnecessary, universally because the almighty God called reason say that and no it is not me, I'm just a slave to him.