Syndicate the full content of your posts, html encoded and add your tags to those posts. Those tags link back to your site and are great to keep spiders that might have only found your feed on the move.
ex. http://www.croncast.com/keyrss/Longaberger.rss
Add an extension to your feeds. Don't leave it empty, leave it as .xml, .rdf or .your-coding-lanugage create a rewrite for .rss - it says exactly what the feed is to a user and extensions make bots happy.
ex. http://www.lifeinthecan.com/episodes.rss
Something to keep in mind if you are doubting feeds can improve your already optimized site, where do you think that most of those Google alerts come from? Hint: It's not your site pages.