I don't know how much you want to spend but I considered these
The Rodriguez Rainier Randonneur Bike
I have a Rodriguez tandem and it is sweet. They make a very light steel frame from OS platinum tubing. I still might go back to steel after having ridden carbon since 1986. I really want a Parlee ESX but $5400 for the frame is a bit steep. I think the frames I linked are in the $1200-2000 range.