Woah, be careful to point out that 5% for Rush comes from either Rush (M) or Rush (L) (I'm not sure which; the wiki will list 3% for M at lv 20, but that's not definitive). There's ambiguity as more testing is still needed. Although I think Gludateon's testing here so far would at least indicate that 5% is probably way above what Rush (S) offers.

Why don't rush weapons get more love then? Because a lot of the rush weapons that also carry assault or pride tend to be Rush (S). Rush (S) is highly likely to be not all that impactful.