I have a small favor to ask to those on the (not) echo group. Can we call "feeds" wafers. Like necho wafers. That would really make my day.
I even promise not to tell everyone I invented the standard if you adopt my idea.
My semi-legit suggestion would also make it so you can somehow provide a css link for your feeds (optional of course) in the description. Having everyone's posts displayed differently really takes "something" away from the experience when reading in an aggregator. It's like you loose part of the personality of the poster when all you get is 12pt verdana, black text on white letters.
Now obviously some people want to see everything in black text and white background, they frankly don't care about the personality of the poster. Their aggregator could just ignore the css stuff.