First off, any off ramp is problematic. You are not going to encourage motorists to pass you on the right by riding off to the right in a bike lane or shoulder. The vehicular way would be to be in the strait lane before the off ramp is even encountered. That way, any vehicles behind can move into the off ramp and proceed without crossing the cyclist's line. Overtaking vehicles going strait would have to merge to an adjacent lane or pass when safe to do so or wait until the interchange was passed.

Otherwise, it would be safest to stop, wait for a big break in traffic taking the off-ramp and cross.