Do not waste primo gems on getting more resin- unless your a whale ( someone who buys primo gems and other stuff with actual money ) you will usually need those primo gems for weapons or characters way more
A lot of the earlier four stars are really good, however the inazuman and sumeru 4 stars are not as good- however if you still like them beside of there downsides in combat or supporting get them
You will probably need to build a physical character later on- since some content is mainly physical dmg based
And me didnβt make a physical character so some bosses I can beat or takes a lot of time to beat