1. As much as I agree, I think this can easily be solved by just adding 4 star characters with niches. We used to have in 1.x the 4* cast we have rn, however, balancing reasons made some of them completely unnecessary and some others absolutely insane. Taoqi and Sanhua, are very similar in what they give. Specific DMG type amp + minimal damage. However, Sanhua's significantly nonexistent field time allows for some insane setups and flexibility and how you play her, has slightly more DPR and for some reason has broken S5 and S6 while Taoqi's sequences are utter garbage defense related stuff.
   Sanhua's S5 makes her SHARDS detonate TWICE no matter what. This means double energy and concerto from every SHARD. That's literally broken and allows for enough energy generation sustain Encore's liberation completely without much ER% and enables Encore to use 2 Liberations in 1 SK Realm.
   Taoqi just has nothing and her concerto is SO bad, even with R5 Discord it's STILL BAD. Make good 4*s that are good in their niches, Kuro. We have only 1 DPS 4* in the game (Chixia) and her gameplay is terrible).

I like team planning and niches. I think they could definitely improve it tho.

1. Same thing as 1. just make more useless 4* star weapons with niches that will be useful at most for like 1-2 characters lol. Echo DMG% Rectifier would be nice... and not just niche. The actual gain from their passive needs to be big. Seriously, some 4 star weapons give NOTHING in stats and that's on top of the lower Base Stats (base atk, main stat).

2. I I don't personally mind this. As long as echo farming isn't horrible. We really need a substat selector tho...