The forum used to have six or seven such groupings, and it did look rather a mess, however much I liked it (hey, it was the familiar - who dislikes the familiar?). The current organisation of forums and sub-forums is based upon Grav's "Gravitised" version of the forums, and personally I think it works well.

I do like your idea about a separate Gaming section, though. If it were me suggesting a new layout, I'd split the Basement into two, and keep the Symposium and Lounge more or less as they are... in fact, I'll list it in your style in the order I'd put the forums:

The Zelaron Symposium
Forum News and Discussion
- Forum Suggestions
- Talk to the Staff
Introduce Yourself
Test Forum

The Lounge
News and Events
Opinion and Debate
Life Discussion
Conversation Forum
The Chat Forum
- World Record Thread
Flame Forum

Gaming
General Gaming
Diablo 2
- D2 Sub-forums
Computer Games and MMOs
- Starcraft 2
- WoW
Console Games and System
- Final Fantasy
- PS3
- 360
- Wii
- PC
Gaming Cons

The Basement
Entertainment and Sport
- Hobbies and Interests
The Arts
- Anime Forum
Automotive Forum
History Forum
Science Forum
RPGMaker
Tech News and Help


"-" denotes a sub forum

I agree that a few names could do with a bit of work. "Zelaron Laboratories" instead of "Science Forum", say, but you get the general idea.