Should we bring back the mouse toss?
I like the theme, but think it would be more fun to change up the game.
Ideas:
Computer case Bowling...
Keyboard Ultimate Frisby

Dodge ball as teams or Half and half?
half n half

Late night Poker???
Texas holdem!! YES

Music during the lan? Yes no?
I recommend no, people's tastes are too diverse...many will be annoyed or simply tune out with their headphones.

Tournements, should we have less?
I am happy with 2 events at a LAN of this size. One 1v1 and a team based game.
My favorite events from past lans (including non LAN OC) were:
Trackmania Nations Forever (LanWar)
Tetris (LAN OC)
Gauntlet of events (trivia, peggle high score, nerf war) (Showdown 2007)
Call of Duty 4: Modern Warfare [Random Teams] (NexusLan)