We've tried many different BF4 configurations over the years since launch. Only the plain vanilla servers ever get much use. In most cases, the others got no use at all (even when users insisted they would get used) and people complained about having DLC maps, so the choice of having just vanilla servers was obvious. Even when we had two vanilla servers, one would be full with a queue and the other would be empty.
For this event, it seems BF1 is getting the lion's-share of attention, so even the vanilla servers are a bit slow.
Actually, only one of the US servers is true "vanilla". The LA server does have the originally free DLC maps.
How about this: We'll add
all the DLC maps to the LA Conquest server later tonight and see what happens. Can't hurt to try it again. :)
Does this mean those of you asking for DLC will be getting your friends together and playing on/seeding the server? ;)