I agree that the Nightingale armor does look awesome, but I haven't used it much outside of necessity.
My current armor for my rogue consists of mismatched armor pieces due to liking certain enchantments. I think it was Volsung, Ancient Shrouded Gauntlets, Dragonscale armor, boots and Glass leggings and a couple of rings and an amulet. I think.
The enchantments are: 50% frost suppression, double sneak attack damage with one handed weapons (30x with daggers, 12x otherwise), Water breathing, 20% better smithing, 20% better prices, and other stuff I forget. In fact it's been so long since i've played Skyrim that I don't even remember if leggings and boots are separate armor pieces.