C-bets

What c-bet % would make you think that there was a decent chance your villian had missed his flop.

If you had also missed, would you fold, call or 3-bet here?

If stakes are an issue, then I am playing at 10NL

I would not 3-bet since that is very difficult to do on a heads up flop when your opponent c-bet (because your raise would be a 2-bet).

Flop texture, and villain's stationyness would play more into this than c-bet percentage. However, a high (80+) c-bet percentage would lead me to raise/float more flops if the texture was right.