Look for a circa 2000s Litespeed. It may not have the panache of a world tour bike, but they have a legacy of their own. No sloping top tube, STI shifters, and if you get lucky you might find one with the Shimano Flight Deck. The titanium frame will last you a lifetime and there's no proprietary pieces so you can replace the groupset if you want.
Mine's 25 years old and I still ride it.