i would feel like a fool dressing the way some chaps do it on bikes.
With these chaps you'd probably look the fool on or off the bike....
That's why you use specific clothing for specific things.
Kidding aside, pretty much you look for similar thing as you do road bike cycle specific clothing. You want something that will take perspiration quickly away from you. You want it to be a material that will dry quickly. You don't want bulky seams in the crotch and upper leg that will rub a blister on you. Loose clothing or snug clothing, just make sure you can move in it. If loose clothing, then make sure it's not going to be caught in something like wheels or chain. Or perhaps snag your handle bars and cause a wreck. I'll always want bright colors so as to be seen.
But you can wear what you like. However the more you ride and the longer you ride at a time, then you might find that you don't care about what non-cyclist's think of your clothes. Three to four hours on a bike and you'll find the mamil look is for a reason.