you should at least be getting decent rb ar PLo20 at Ipoker, so just keep grinding that level, rake isnt significantly less at PLO50 from what i remember
Rake is of course beatable at PLO100 and at smaller stackes.
If i have a table full of fishes i would easily agree to pay 10% rake, just to make sure they stay.
Having a nice rakeback deal as well helps for sure. As a Supernova at stars, which is easy doable at PLO100 you get almost 40% rakeback, so this adds 4bb to your winrate at PLO100 (if rake is 12bb/100 Hands)