This is too broad a topic to have any meaningful discussion on in a comment thread, but I'd start with a few things:

1. Are you looking for new perspectives, or are you looking to debate? The former implies you're willing to change your stance, the latter does not.
2. Define "capitalism", "communism" and "good". As a minimum to starting such a discussion, everyone participating should be on the same page regarding the topic, but these are terms that have wildly different meanings for a lot of people (not so much on this instance).
3. Pick a specific theme to discuss - what do you support most about capitalism? What is your greatest issue with communism? Anything you're specifically interested in? As I said, it's a broad topic, so in order to have any constructive discussion, it needs to be narrowed down.