As much as your hands have to play on an arranger (playing rock organ, you often had a hand sort of spare to play the half moon switch, on arranger that hand's pretty busy playing chords), I think that multi-switch footpedal setups are perfect...

Leslie F/S is ALWAYS tasked to a footswitch in my setup. As is Variation select (with auto-fill on) and whatever the gig needs (I can create custom UPS's with different layouts for live, arranger, and studio very easily), like Registration up/down, UPR/LWR sustain, sostenuto, Breaks, you name it.

My hands are best used for playing!