Thank you for the links, I am in fact considering leather for both saddle and grips.

I am quite familiar with the BWR now. My pursuit (since 2007) on a faster Brompton took me far from the 6 speed model before the BWR was introduced. It might be a good fit for me. I am most likely going IGH, or on a conventional bike (Alfine or Rohloff) or on a Brompton.

Still working on the money aspect of it.