Optimized kit upgrading

[Senkowo]

I didn't play in a whileee, so I don't really remember what the most efficient combinations of blue kits, common kits, and blue and common items are anymore, could you help me out?

[GoldenTX]

Rare power units are most efficient, but if you have a spare epic or legendary one definitely max them out before using them.

[Burn Baby Burn]

max common kit=3 rare cards + 6 common cards
max rare kit =3 max common kits + 1 rare card + 3 common cards