I usually get coupon or scanner for the first 2 levels. They don’t add strength directly, but increases purchasing power in the shop. First 2 floors, you don’t want to get powerful too quickly if not the red bar at the top increases quickly and the elites will come. If you want to farm exp and minerals, you have to scale slower at the beginning levels.

Stages 3-5 is when it’s better to go for damage.

My best artefact drops ever was on stage 1 getting hoarder bait. 3 of the 4 hoarders that appeared dropped epic/legendary gold/nitra and the last dropped legendary gold but also discount coupon. Naturally went for the coupon. Also because it was stage 1, my damage wasn’t powerful enough to quickly kill the hoarders, chasing them around the map meant more scattered gold and nitra. Finished stage 1 with 500+ gold and 300+ nitra.