Bet Size - bbs or $$
Analyzing my own game at $0.01 / $0.02, one of the leaks I see that should be easy to control, is I look at bets as a cash value instead of as just bbs, or a portion of my stack.
At times I find myself calling low bets or raises thinking "It's only a few pennies". I need to train myself to look at it as "It's 5 bbs, or 5% of my stack" instead of "Ahhhh hell, it's only a dime".
I feel that Micros are the place to learn the game, and it's just one of the things I need to learn and pay attention to better, which hopefully will lead to better and smarter play and stack management at higher levels.