What Sine said. Wings are pretty much a excellent way to permanently increase your stats and they also look awesome when you upgrade them. They both permanently increase stats and get bigger and morph after certain levels.
Thanks for being a awesomely helpful and supporting member of the community, but the Aeria Games Wiki page for wings is here
and does show images and stats of most wings (empty spaces added soon).
Main page for the CS wiki is here
. It's constantly being updated and already has more detailed information then that wiki. We're also pushing wiki information onto the forums so be on the lookout for that.