Can't imagine you'd be real popular out there at Kermas. There's a wave just South called KFC that's about a 10 minute walk that would be ok for SUP I reckon. Usually a lot less crowded than Keramas. Also the next bay to the North called Cucukan. (Pronounced Choo-Choo Kan) that's a point style wave that goes into deep water that would be SUP heaven. I wasn't sure about posting info about a once secret spot here but I googled it and it looks like these days it's about as secret as Snapper Rocks.

Forget the SUP at Keramas. Was not well received at Serangan so I can imagine Keramas would be 10 times more localised.
I'd be hitting Oka point if it's going to be that big. Safe SUP wave breaking in very deep water and long rides

Yeah mate just south a bit. Spot I've surfed many times alone, dunno why? I call it black magic. Black sand and no one else. Needs better than average swell n mid tides. Been in bali for two weeks surfed there 4 times shared once with three (I'm on a mid length) they were on s/b. Good sup wave but. on way home now dam it. Enjoy