Well when it comes to lag, there are so many factors, such as Your server Host, Other script that you might be running, also the custom races that you might have on your server, maps ect...ect. alltho, it should not lag as much as every one is blaming wcs to be "lagy" mod if you have just right settings. I run 20 man server with no lag at round start and I save levels each round which should give me lag but fact is it does not give me lag at all, but then again I have great hardwares on server and most of the player who are in my team or regulars on server have really descent computers. Well anyway lets get you setup with no lag WCS
So lets try every every thing one by one.
For testing host Download HLSW and add your server to HLSW and then enter rcon password, and then click on "get log" ( If you need more help on HLSW you can visit
http://www.hlsw.net/ and find out how to use HLSW...) After it says "Successfully receiving server log" type stats 5 times in console delaying about two seconds each...
and it should give some thing like this
10:21:31 stats
10:21:31 CPU In Out Uptime Users FPS Players
4.80 5924.15 8330.03 2472 76 327.33 2
So copy those results from all 5 times and post here.
Now for other script I did try to look up what else you were running on your server beside but your server was down so I was not able to get those data, so just post here what other scripts you are running beside wcs.
For races, back up all your current files and then clean reinstall your WCS mod with no custom races, just only ones that come in the original wcs package. and see if that helps...
if every thing above fails then try to run server on standard maps and see if that improves lag...