Unless ag is expecting a miraculous (and permanent) rise in players, numbers are only gonna drop for now, especially with the insanely slow pace updates are being put out. Even high pop servers have issues with enough players wanting to group up and so things and the only solution is cross server queues.
Ive heard a expedition finder is going to be implemented soon so this should definitely apply to that as well, but OPR is IMPOSSIBLE at most times, even though Im in a fairly populated server with a ton of PVPers. I really dont care about the idea of keeping everything in one server, If anything you can make it so people from a specific server get put in the same match, but its not only limited to just the people in queue on that server.
Ex, lets say there is 20 people in queue for my server, when I enter, Im put in the same lobby as those people, but it also fills the rest with people from different servers.
This way, people from the same servers can play together, but dont have to wait in a cough**cough 2 hour queue to play 1 game of OPR just to be put back into another long queue after.