I started playing Nutaku Aigis since the very first day, got an army and got to the shrine with the tutorial summon (kerry at the time, Bashira now) and later rolls were, in that order: Bashira, Jerome, Sheril, Calliope, Valerie. But then i used CE and the great "accounts rollback" for cheaters so i had to start over, i really thought of rerolling accounts until i got a black so i could have a head start. But i decided not to; first months of premium rolls were all silvers (i cannot stress MONTHS enough) and i already flew throu the maps since i already new the layout, enemies and all that. It was when first Anya event came and i managed to barely get enough stars to beat the event. Then i got something other than silvers, i got my Sybilla, not just any black but my waifu; i quickly got her to lv80 and fed her all the rainbow fairies i got. a few events later i got Nanaly and i use her on my main team ever since.
I don't use Sybilla on the first run of any map, nor use Nanaly's skill; i like to have a feel of the map before deciding if i need OP blackness or it can be done with the main team. It's all part of the fun, and eventually you will get the units you need and some of the ones you want