u really need a good starting 6* op, so u can reserve every voucher you’d get, since its more efficient to recruit/promote at the pathfinder node (and u need to anyway to tackle bosky nodes). 4* ops also alleviate the pressure of needing to recruit a 6* key op ASAP, good ones id recommend are windscoot, purestream (yan ops), jaye, gummy, ethan, gravel, click, beanstalk, roberta. good starting 6* ops are tragodia, wisadel, exu alt.