It sounds like you are making very large bets if you'll have less than 2 cbets when you start with a stack of 20-30 bbs. If your standard bet is large then I would treat your stack more like a short stack. If it's the standard 3-4x the bb if you're dominated you might lose half your stack, but you still will have a decent opportunity to lay the hand down and find another spot to shove and double back up. After the flop the best, most straight forward way to play is bet if no one else has and fold if someone else bets or raises. This is what you should do if you don't have any other information. But these are the situations you should really use the information you've gathered on your opponents. How likely are they to call any c-bet, chase hands down, raise, etc. You should be trying to pin them down on specific hands they would have had to enter the pot with. If you are up against a tricky player, it's better to lay the hand down and wait for a better spot against more marginal opponents who you have more information on.