My legs are just a little bit longer than yours (depending on the method you use to measure your inseam) & the standard post was *just* a bit too small.

I'd go for the 6 speed. I live in rolling terrain & while I could manage with a 3 speed, the extra range makes for a much more enjoyable ride.

We are about the same height. I've got the M bars, and they are maybe an inch below the seat level. I've got sensitive wrists, but this setup doesn't bother me. I suspect it's because the cockpit is shorter so I've got less weight on my wrists.

Hope that helps.