How about a feed debugger, a way of getting a preview of how FF will process a feed, immediately. Otherwise you have to wait until it decides to reload the feed. Also, how about picking up <description> elements. Seems a shame to ignore good metadata that's sitting right there.
I made the suggestion about descriptions months ago, when we were working on NewsJunk, and couldn't use feeds and fell back to using the API. They could just bake into their code what we'd have to do through the API. I don't think there are that many people doing custom work for FF, and I hope it's not to arrogant to think I'm not just a random feed guy.
- Dave Winer