My first piece of E80 advice, bebop, is get an FC-7 footswitch if you haven't already. It makes for almost 90% hands-free running of the arranger without taking your hands from the keyboard (probably 75% of all arranger mistakes come from taking the left hand off the keys to hit a button, and then dash back for a chord change).

I even use mine for sustain, too. I just carry the FC-7, no sustain pedals (although I am thinking of going back to regular piano sustain pedals and getting two more functions on the pedal). At the moment, I use mine like so, from left to right

Var 1 (change auto-fill from the front panel, usually on)
Var2
Var3
Var 4
Lower sustain
Upper sustain
Leslie Fast/Slow

But I'm sure you'll have your own priorities. Just get one. I couldn't gig without mine, hardly....