Try this; when you start up ET, hit the tilde key ~ then type into the console "connect et.pxclan.org" and hit enter. If you did it right it should bring you to an ET server that doesn't have any ridiculous mods, or abuse mods/admins(unless you're genuinely being stupid) with many great maps to play on. There isn't always a lot of people to play with but most night's between 5pm-10pm EST there are about 10+ people playing(some nights it can get up to 30 people playing) and Weekends generally have at least a few players during the day, especially Sunday.
I believe they run ETPro, not many modifications I don't think, nothing that really stands out anyways. The people there are fairly decent though, a few of them are almost godly when they're playing seriously, but there's also a fair number of newbies as well.
One thing I'd like you to keep in mind if you can, try to keep teams balanced. If the teams get severely unbalanced it snowballs until the underdog team becomes unstoppable from all the high-level players that join in desperate try to balance the teams. This server tries to take things seriously in making the game fair and trying to get people to enjoy their time playing there so they'll come back again.
I've played on this server for years, in my opinion, it really is the best public server on ET. And in case you're wondering about the way I told you how to connect to it, rather than finding it on the server list or by typing in the IP address is because they occasionally change servers and routing your connection through their website it ensures that you'll always be able to get there even when they change servers.
And one last thing, even if you come to this board and this topic is locked, go ahead and try connecting anyways. Chances are that if there are still people out there recommending you to play Wolfenstein Enemy Territory online, this server is still up and running.
Thanks for listening, and please enjoy this server. Please note I am not part of the clan that runs this server, just a really big fan.