Actual conversation that recently took place here:
they: (twirl in dress) "How does this look?" we: "Very pretty" they: (disappear, change, twirl in different dress) "How does this look?" we: "Very pretty" they: "...are you ever going to answer anything other than 'Very pretty'?" we: "Well, you are very pretty. You are very pretty when you're stuffed-up and puffy from a cold, have bed-hair, and are wearing an old T-shirt and yoga pants". they: "...you're going to be completely useless if every time I try on an outfit ask you 'How does this look?', you answer 'Very pretty'." we: "Well, if you have two outfits, I can tell you which one I like better. That first dress? Much better." they: "...I'll send the other one back."
Also, when I was doing a lot of running, one of the things I really liked was bike-shorts-length spandex underwear. It's very comfy, and it prevents chafing in the Parts Region. Then you can throw whatever crappy shorts over the top of those, just so people aren't exposed to my spandex-clad Parts Region.