When you gig in live situations, do you use vocal effects?

I find that most vocal effects like chorus, pitch shifters and so on are impossible to hear if done subtly and correctly (like during a recording), and too wild if you turn it up to hear it over a crowd or large room. I am even having difficulties setting up reverb and delay when I don't know what the gig is going to be like. Are there any good answers or places to figure this out?