Anything that sounds good.
Since the 1980's, I switched to all M.I.D.I. Implementation, but man, there are too many unique foot pedals than no multi effects unit or rack processors can emulate , so I got a Decibel Eleven Loop Expander to include foot pedals with M.I.D.I. control.
My favorite pedals are ; the Seymour Duncan SFX-1 Pickup Booster ( got two on my board), Arion Hot Watt 2, Behringer AM100 Acoustic Modeler ( sounded better than the Boss AC2 or AC3), Electro Harmonix Ravish pedal, Digitech Freqout pedal, MX 10 band Eq and Boss GE-7 Band Eq, that are in my Decibel Eleven Loop Expander's loops .