Do you think it is better to place unique articles only on your home site, in article submission directories or both? I ask because I thought if I had the same article on my home site as I do in a directory Google could penalize me. What is the general rule of thumb on this?
I think it is just duplicate content and waste of time. Why would the users want to see the same article in two places?
Why don't you use your homepage to display short descriptions of your article pages? Don't include the full summary of your articles. So, I'd recommend having them in directories.
The new Google algorithm hates that. It is best if you have original contents for your homepage if you want your site to rank. You must also understand that contents for linking must be different from that of your homepage. Avoid duplicating contents because Google will treat your home site as scrapper site. I hope that will help you.