All QoL options should be opt-outable. If you choose not to use them that is on you.
Stacking currency, Loot Filter are easy ones.
I get the qualm about P8, I would use it, but I think it is another thing that takes away from pub games and cooperation. I couldn’t care to truly argue against it. Perhaps max benefit from P7 is the P7/1 drop rate rather than the players 8/8 drop rate? I don’t know. Just always liked working together.
As for balance I don’t think it is controversial. Some builds and skills are trash. Not everything has to operate in the exact same way, but everything should have potential to at least be good. Meanwhile there are some S tier builds and builds that even with the most god tier gear couldn’t even hit C tier. Some of the abilities need to just work differently, some of them need a way to improve the maximum damage. Just depends.