I know you would prefer a reply from the policy makers on this one LL, but I'm going to take a swing at it, because I think I know the answer.
The stock reply to this kind of question is characters are given their own forums depending on how much play they get on the boards.
So why would characters like Eve and Gwen have their own forums when more posted-about characters like Lindsey and Lilah don't?
At the time of their introduction Eve and Gwen appeared to have import to the series. They were posted about. I believe Eve had a credit as a Season Five regular. They don't get posted about much anymore though, right? You may have a point. Here's the thing though. There are many more details concerning the administration of this board being considered at any one time. Stuff like the Eve and Gwen forums can slip down to the bottom of the schedule of things to do. On the other hand it may have been discussed and there may be a reason these 2 characters still have their own forum. We'll both have to wait to find out if that's the case.
On Lilah and Lindsey, again you've got a point. They still get a fair amount of play, and possibly they could handle their own forum. Here's the thing there though. If you take them out of Wolfram & Hart do you still need a Wolfram & Hart? Having those 2 characters in that forum allows a grouping of characters in a single forum. Nevertheless it may be that things have changed to demand a separate forum for those 2 characters. I'm thinking it will eventually get discussed by the admins, but again, give it time. It takes time to get around to that kind of thing. I mean Jeez Buffy just re-organized the whole board dealing with a slow-down problem. Stuff like this has to wait a bit.
Personally, even when it does come time to discuss it, I think it may make sense to leave the W&H forum the way it is. Not to worry though LL, I suspect my requested input will be minimal on this matter.