Another vote for used. No, you do not buy used bikes in stores. Yes, caveat emptor always applies. If you can solve the problems any commuter has to solve every day you can manage friction shifting. It's been done for 95 years and somehow we survived. Commuters want reliability and simplicity. Older bikes have that in spades.
Same bike for gravel and spirited long rides and commuting makes no sense. Do you have parking at your desk? Do you imagine you can do a long gravel ride on Sunday and the bike needs zero maintenance every time? The bike is just ready to go Monday morning?
Suspension and reliability can sort of go together. Long term? See a lot of old suspension on the street?