All units listed hereafter will be in leveling priority order, as well as 100% affection ASAP

get bernice to 50CC60 asap. you need heavy armors for upcoming event, and leeanne to CC50
bashira to CC50, then use 2 plat armor (with fairies) to get her to cc61.
then get sasha to CC50
fedora to cc46
Alissa to CC50
mehlis to CC46
yuyu to cc46

thereafter, get the above to max levels in the same order (including spica when you get her; bashira can wait until you level 2nd bashira to 30CC10 and use 3 plat fairies to combine for max exp)
Then work on the following:
Julian (2nd UP generator)
Cloris (2nd/3rd witch)
Conrad (HP soak duelist)
Vincent
all current cc'd silvers to cc50