The <hr /> that separates posts from signatures is uggo. Currently it is this very on the nose #d3d3d3 which is brighter than post text and makes the post not flow gently into a signature but separated with THIS MASSIVE GIGANTIC WHITE LINE
I suggest making it a little subtler, with a dimmer gray colour and more margins on the sides so that it actually looks as it should. Also, we could restrict max width of the hr to be 700px to make it the same as the max sig width in the rules
(To do this, find the global.css stylesheet and around line 2143 find the hr.signaturehr class and replace it with this