Eh, this is just true of most idle games I've found. The SR's are worthless and not used outside of your initial start.

Am enjoying the gameplay though, for sure.

It's crap, but Nikke is far from the only game, or even gacha to do it. Will always criticise it though, and noted it in their survey that it's a load of crap. Just let people push as far as they can, even with an underpowered team.