Any endurance road bike with decent components will do. I consider Shimano 105 decent, Ultegra really nice, DuraAce excellent. Tiagra would be acceptable on a budget. If you have the choice between C.F. with Sora and aluminum with 105, go aluminum.
Endurance road will be slightly more compliant than a racing road bike, and slightly more relaxed (comfortable) geometry.
Flat bar road bikes are ok too, unless you find yourself wishing for a more aerodynamic position on the bike. Riding on the hoods is more aero than on a flat bar. But a flat bar may feel more nimble at first, and less stretched out.