US player here with an outside prospective. They said merging the servers to one would not help the population, but shouldn't it be the players choice if they want more people to play with or less ping?
Then he mentioned not wanting to upset the PVE vs PVP vs RP crowd by sticking them on the same server. But for a small community like Apac, I think they can live with the tiny inconvinance. If you want be a PVP player, flag up all the time. Solved. I heard RPers do do in their own private chat/guild channels, they wouldn't be bothered. And PVE players would go unchanged.
Give these players a choice. Merge them to one PVE server AND offer optional FREE transfers to those who would like a larger population to play with. It seems almost to simple to do both options. Give them at least one server.