I have two "all-rounders", which I determine as a versatile bike that can ride any road surface with decent speed, and carry enough stuff for a day's adventure.
One started as a Rivendell road bike, now with 650x38b tires and moustache bars.
The other is an old Schwinn KOM, a racing MTB. Now with 2.1" semi-slick tires and drop bars. This bike excels on gravel.