Another popular choice on gravel and all-road bikes is the 1 x
(say "one by") groupset, a familiar concept to modern mountain
bikers. This just eliminates the front mech in favour of a
clutch-style rear mech with a much bigger range. The gaps between
gear are bigger, but the gear range can be enormous. Lower
maintenance, quieter running, cleaner looks, 1 x is really gaining
momentum. SRAM have been pushing this for a while, and this build
uses their Force One set up with hydraulic brakes.