Friction drive is definitely the simplest, most hassle-free
way to go. The only drawback is slippage in the wet.
Where I live, it gets really soggy 7/8 mos. a year.
Happily, I fabricated a pretty bomb-proof roller, and
that failing, my Dax converts to a DIY belt drive in
about 30 minutes.
Actually, now I've 2 bikes, one Staton Friction/GX35,
the other, the Dax belt setup/Tanaka PF4000, both
with really low ratios that will cruise lazily at 15 mph
up almost anything.