"Do you really want that many new tournaments showing up on your tournament selection screen? You could have 150+ tournaments available to join at any time."

Yes. Please. :-)

"Might look a bit cluttered."

That's where filters might come in.

And I agree with everyone who said that making tournaments public be the default.

I am in the process of making it so that all tournaments created by users will be available to all...

This will take some time, as now I need to create a rating system and figure out the best way to make this all happen.

Imagine this site with, let's say 10k users. 500 of them likes to create tournaments. I want to have chance playing their maps. What's my chance if I'm not in top...hmmm 50? [what's the chance that they added me as a friend if I'm one of 5k ppl with lvl 18?]
Now imagine, theres 20k users :]

Idea with rating system and few (dozens ;p) pages of tournaments, sorted by rating ofc, is the one I agree with :]

Question is: if we have like 300 tourneys, sorted by rating, where will be new tourney placed? I hope that not at the end of the list (at the 15th page for instance). Brainstorm? :]

Ya, this is why this is more complicated than one might think at first. :)

Keep the ideas coming :)

The placement is not that difficult. For example look at kongregate.com

They have tops in categories and new games. Just do something similar. You can still change the layout later - that shouldn't be too hard.

The rating system will be the bigger part.