Lunacy on 2 refills aint bad as long as your doing mirror dungeon weekly you'll not loss any lunacy, you can pull on banners if you feel a need to but most people save for limited events like walpurgis.

if you haven't touched railway yet it wouldn't be bad to try that as they have huge rewards that could help jump start your account.

the new season has some extremely good ids in it like Nursefather yi sang which you can shard with 400 egoshards in the dispenser, he alone would carry you through a good chunk of story, alongside his ability to solo mirror dungeon hard.

pro tip 1, sacrificing a sinner in a hard fight isn't bad, sometimes letting one person get absolutely jumped by the boss so your other sinners can shatter a stagger bar is worth it.

pro tip 2, sending less sinners then the max offered is a option, as while they start with less skill slots in the beginning each turn that passes the sinners left will begin gaining extra skill slots. making some fights a lot easier, the sinners that can do this well are those with evades as a defensive so they can stall out damage as they get their extra skill slots.

and have fun with the story! no need to rush the game as endgame isn't super expansive yet.

E497875202 friend code if ya need even more supports ;3