Any tips on the most efficient way to farm equipment?

OopchoAhsa

So far, what I've been doing is farming the equipment I need mostly on Normal level so I only use 6 energy. Unfortunately, I sometimes go through instances where it would take 3-5x attempts just to get a single piece of equipment and I feel like I am doing something wrong.

Qeltar

You aren't, the drop rates are just low.
Be sure you collect regular shipments every 6 hours, they are a good source of gear.
Also, check for hard missions with character shards you want that also have gear pieces you need.
Otherwise.. be patient, and if you can, do at least the 50-crystal refills.