I reckon it'd be cool if players could start a vote for a track they like, something like this:
Steve types /startvote clip
"**Server: Steve suggests Clip as the next race. To vote for it, type /vote" (or some other command since /vote is already in use)
If more than half the server votes in favour, the race gets loaded. This way, players wouldn't need to spam admins if they want a race loading; they could let the server decide for itself. It also means admins don't have to be present for races to be loaded. It's win-win
Only possible downside is overuse, but that can be easily fixed by making it so after a suggested race wins the vote, the command can't be used for another 10 minutes/hour/whatever