#1 Dutch Tilt is distracting. There are situations where it can enhance a composition, but not here. It actually shows less of her costume. Here are some tilts I did, that seems to work well:http://www.cosplay.com/photo/2346981/ http://www.cosplay.com/photo/2231422/ http://www.cosplay.com/photo/2126237/
#2 I agree that cropping the feet was not a good move. You could should wider an crop it to a square or similar format. I am not a fan of busy backgrounds, but I guess you are going for capturing the event feel.
#3 I do like the low angle, tight crop, and simple background.
#4 The tilt does not bother me here. The straight on pose seems kind of boring and makes her look wide. A lower angle using the ceiling as the background might have been more heroic and have a cleaner background.
#5 Harley's pose is nice. The bright carpet pulls my attention..Again, a lower angle for a better background...but be careful...I find low angles usually work better when they are not looking down towards the lens. Otherwise, double chins and bags under the eye can happen.