Politics wise, I think human. It's a safe choice, but by the 24th century humanity has evolved past most of the main problems that affect our race in the 21st century, namely capitalism and all its symptoms like scarcity and homelessness. They've also put a priority on research and exploration along with cooperation with all races, even patching things up with other races and cultures that they were previously at war with, like the Klingons.
Durruti wrote (edited )
Bajoran. I think its because their culture is one of the ones explored the most in Star Trek.