EDIT: I slightly over-exaggerated the problem, being frustrated as I was, but the issue still remains nevertheless. Just not as bad as my upset self proclaimed it to be. But it still does make players leave at times, sometimes a great amount of them.
I noticed today, while mainly playing on D2 that the teams would occasionally get severely stacked skill-wise. Nobody usually does anything, even when people say something about it, and that just makes the pubbers mad and leave. In a round or two after that, several players have usually left, sometimes half the entire team that was complaining of being stacked against. It basically clears out the server, cuz the people on the other team don't like playing 3 on 3 or so, when it could have been fun before the other 4-5 people left.
Just wanted to point out that little observation there...
I've gotten so frustrated at this before that I've just left the server, which is a rarity for me, since I usually play through hard times. And the sad thing was, someone said teams are perfectly fine when nearly the whole T team had no idea how to play and would stand around and do nothing really.
That "Smart Team Balance" plugin might be a good idea if this server is gonna stay alive for longer periods of time.
I love playing on the D2 server, but it's always empty, and then when it gets people in it, this issue happens and they just leave after an hour or so, giving just a short time to actually enjoy a good set of rounds on D2.
I know there's plenty of other reasons why it's hard to get it full, but this is one that I see all too often and can be prevented easily. It just needs the support and work of the community to do it.