Dunno if you have beaten the game already (since it's been a year), but if you use the right strategy, even powerups become irrelevant.
Try upgrading the fairy in the clinic. The -2 manacost and chance to eat quickly makes them superior to the Naga and Deertaur in most cases.
The Naga engineer that build generator is a must if you wanna win. Build it in the nearest tiny exit spot so no tinies can interrupt or destroy the generator. Then try to obtain the Naga that halves your spell manacost. After that place the voracious traps (FAE TRAPS spellbook) near the generator and now you are kinda guaranteed a perfect run in almost every stage.
Also, the ECONOMANCY spellbook is very op. Try to unlock it if you can. Moreover you can equip multiple spellbooks at once, so you have both ECONOMANCY and FAE TRAPS equipped (however, there is a cooldown when you switch books). With this, even the final stage shouldn't be difficult even if you don't pick any powerup. The GIRL ENHANCEMENT is also a nice book to have in case you want to dismiss a girl in a space to switch to a better girl.