A server merge would be great, but the main down side I see is it will restrict rolling new characters, for example I have 8 on the Jedi side on one server and 8 Sith side on the other, so I can see what all of the classes are like, and combined I'm 4 over the 12 limit.
I have some level 1 toons I have not used yet, and if they release some new class I can re-roll one. With a merge I'll be over the limit and not be able to check out a new race or re-roll one I have unlocked. Maybe if they took had the same system as GW2 and allowed us to buy character slots it would be better.
It is practically dead on the AP servers, and the only game with less players is The Secret World. At times I think I should have stayed playing on the US servers and then I'd be on "The Harbringer" with a high population.
Playing on an AP server you have to feel a bit ripped off at the moment, all other servers got mergers and get 12 slots and we have only 8 and are ignored because we are in a low customer population area compared to US and EU.