On completely new account, that will not see good free archers and melee rangers for quite some time, Spica and Saki are godsend.
And, Awakened units are mostly not that needed just yet, outside of a Daily G runs. So I'll mirror the general ideao of the thread: Spica, AW Spica then Saki.
Of course, should your premium luck be extra generous with platinum (not blacks, they way too expensive to max-level) unit with good passive multipliers, slot in another AW fairy before Saki, but no more than one.