I remember a girl that was a Weeping Angel at Otakon last year. It was great! Go for it!
And you know, you'll have the obvious poses for when you get stopped for pictures, but the costume also lends itself well to stationary poses (duh :P) for when you need to take a break from walking around, so you have that going for you as well. Just stand in a corner where it's not easier to notice you and "weep", and every now and then stealthily change pose or move to another corner.
Brave: Merida [Halloween]
Digimon: Joe [Otakon 2014]
Gundam Wing: Duo Maxwell [Otakon 2014]
Kaichou wa Maid-sama: Misaki (Maid Latte uniform) [Otakon 2014]
Adventure Time: Flame Princess
Chihayafuru : Chihaya (red/blue tournament outfit)