The Tournaments area could just hold two-rounds "events".
Make a different area for leagues and other gatherings too.
Any chance you'd consider updating the forum to the latest phpBB version? It's offers an extra level of subdivisions so you could separate the course discussion area to hold threads for each individual course, each tourney has an area, etc. Once a tournament date has passed, I relocate it to an archive area.
Check out how I have the DisCap forum laid out. http://discap.net/forum/
I also had some input as to how the NEFA board is laid out, although that is a much bigger scale with course threads divided by state and 2-3 tournaments every weekend. http://forums.nefa.com/