I tend to like "realistic" armors more. When I'm exploring in the wild or dungeon diving, I wear Blades armor, Ebony gauntlets, steel boots, and a Nightingale hood. http://i.imgur.com/gbPnC.jpg.
When I'm about to partake in a proper battle (against a dragon and such), I throw on a Blades helmet and look, in my opinion, http://i.imgur.com/rKiaN.jpg.
However, I've been using this armor combo since November and only just now noticed http://i.imgur.com/DyapL.jpg. Made me so sad, now I can't stop seeing it.
I keep fine clothes and boots in my inventory for house/normal wear, but I don't stick around long enough to actually bother changing from my armor.
Edit: If I'm using stealth, slitting throats, or otherwise doing something that doesn't quite fit the nobel look of Blades armor, I wear Nightengale or Ebony Mail.