You could have a look at the comotion mocha.
It ticks of all of your boxes: 650 2" tires, dropbar setup and a 2x 11 drivetrain. It costs 4000$ without couplers.
We've made the similar experience that we are mostly limited by comfort rather than edurance. But we have a steel frame and can fit 32mm, it only starts to get painful after 60 miles.