current ratio is 3 lv : 2 nest. The reason why nest is important is because it prevents the biggest problem I've had, which is getting attacker(s) early. This matters as often t1 I'd end up placing energy for turn on unown or something because I need draws badly. Putting extra attackers in the deck isn't the answer, as you can end up with dead unown in hand feeling pretty stupid; more importantly nest ball can give draws. 4 ultra 3 level and 2 steenee, I really don't have any trouble finding the pieces for the combination; the follow up game is what needs improvement.
Potentially using "tech" attackers, e.g. absol (ik not released, I'm sry), its a lot easier to find the one you want, and generally 4 trainers' mail gives a lot more choice.
The deck keeps steenee in hand once you draw it; Only discard outlet is ultra ball.