I think the OP is a bit late asking for advice. That bike is a 57cm and he is like 6'1" ??? That high stem is a death trap. IMO
Looks like them goofball LHTs. Great bike for the right size guy.
Otherwise a 32T rear would be fine, biopace I dunno. Chopping the high end 50T usually only gives you useless stupid duplicate ratios.
My Rohloff was 23 to 120 GI pushing 130 lbs. I was passing farm wagons, some dump trucks going uphill and Honda 150s going downhill. LOL I'll leave the 92 GI highs for the sisters of the poor.