This looks like exactly what I need - I have been wanting people to submit articles for months, but can't quite figure out how to make this happen.
I already offer a free backlink with each article, so this will not be a problem. You can either have it placed in the main body of the text or in an "About the Author" section at the bottom like a standard article directory. I typically leave all links as DoFollow unless they are affiliate links that need to be "condomized."
As for topics, I am particularly in need of Internet marketing-related posts (may cover any of the subtopics that you mentioned), although I wouldn't mind a few libertarian-themed political posts thrown in there as well, especially with our national debt having surpassed $10 trillion :)
If you would like to submit an article (or "guest post" - it's pretty much the same thing), just go to the Contact page at Karlonia.com and paste it into the box.
Current traffic levels at Karlonia are running at 600-800 unique visitors per day on weekdays, dropping off to around 500 on the weekends. Approximate breakdown of traffic is 80% from search engines, 10% from Entrecard, and 10% from direct traffic and other sites.
Meanwhile, perhaps I need to put up a separate "Submit an Article" link on my top navigation bar instead of just the Contact page that I am using now. Hmmmm...