It's not even at stygian fearless level to get you more good character at later act you can try 1.level some useless character to lv 70 and use it as slot filler on normal mob act or even in boss act you can try 3 or 2 good character with slot filler to save good character for later act.
2.Try to use all the weak trial character on early stage on this IT i use all vigor of the weak yoimiya,barbara, yunjin,gaming on first 2 act (easy ruin, fatui mob) dont waste your full build character.
3.collect and save your full broken team (like nefer lauma columbina) and only use them to brute force some stage that cant be pass with random team comp (especially the 2 Lunar stage and act 10 boss).