The new bigger cassettes make it possible to get good touring gears with a regular compact crank. So my approach to customizing something like and endurance a bike for touring is to stick with the compact crank and go to a larger cassette and install a higher capacity rear derailleur.
That is a good approach IMO and I'd probably do the same on a new bike if I didn't go with a 1X10 or 1X11.
That said I used a narrower range cluster because it was an old 7 speed bike. I might have reset the frame for a wider rear hub except it was an aluminum frame. That gave me an okay range, but no really low granny. It still worked out fine for the ST packing ultralight camping gear even with the limited gear range.