Try riding your single bike as slowly as possible & take up unicycling and that seems to help a bit at riding at slow speeds. I think I've got 30 front, 32 rear, no problems on stability, but we could use lower gearing on occasion. Normally don't get below about 5 mph, but stability isn't really the issue, either. On my single bike, I can ride under 3 mph okay. I was riding with a recumbent lady one time, and when she went to walk a hill, she was surprised that I could ride at her walking pace.