My systems only trade based off price-action, so price pivots (aka swing H/L) are what they rely on.
I have always used fib ratios (retracements & expansions / extensions) as a way to dynamically adapt entry/exit levels to volatility.
Ironically, I never trusted any classic indicator as they are much obviously dependent on number of bars printed, which itself is very sensitive to the "noise" level in a market ... Then I found the hard way that price pivots (again, swing H/L, *nothing* to do w/ so-called "floor pivots) are also very much dependent on number of bars printed, as a result almost as much sensitive to the "noise" level. I currently use a combination of price, time & volume to identify the pivots, with quite a bit of complexity akin to fuzzy-logic.