I've done a lot of experimentation with different cycling pants.

After long research, I'm leaning towards wearing regular jeans or dockers. The trick is to have jeans that are a little larger and then make sure the belt doesn't make them ride too high. In fact, I'll often loosen the belt entirely to let them ride wherever they need to.

But of course this is a very personal matter that changes with temperature, length of ride, type of jeans, etc. etc.