Well I decided to go with higher ohms, and wound a coil for .88 ohms after taking the tank completely apart, cleaning it in hot soapy water, and putting in a new wick. I tried the burn-off method described above, but 40 minutes later that coil was all gunked up again, with a crust of carbon all over it's top coils. I think it might be the gunkability of my juice, plus the .75 ohm coil I was using. Further research is called for.
Getting good vapor and flavor at .88 ohms so far.