Love the idea of tournaments, Maybe have some even for Gta4. You guys should get in touch with Rockstar and get them to send you some stuff to give away (t-shirts, Stickers, posters, etc) I don't think they'll mind, giving away stuff once a year for a larger community seems like a pretty good deal.
Its sure to get more people interested and take it a bit seriously.
Also I'm just gonna rant on a bit here,
Lack of commitment to the server is not exactly true, Couple of us were pretty much always on (Wrx, Earthbound, Noru,etc), I guess the development side was a bit slow, then again we were all pretty new to Lua and were still learning. Fairly sure that it was the which server got really unstable towards the end (Going down for hours, not showing up on searches) After which people stopped going on.