A lot of people here don't understand that it's not the players' job to make the game work. It's broken in it's current state, and Square is responsible for fixing it.
I don't care how difficult it would be to implement a cross DC party finder, they either need to implement it somehow, or remove DC travel. It's downright terrible to be a raider based in Crystal. I've tried reviving the raiding scene, and it's left me sitting there waiting for a PF to fill for 10 hours on a saturday for a raid with ten PF entries over on Aether.
What annoys me the most is the people here who just accept that this is the only way it can be instead of considering that it can be fixed.
You want a solution from me? Have all DCs within a region access the same cross DC Party Finder. This could be hosted on one of the already existing Data Centers, maybe separate from the Cross World PF. When you join the party, it prompts you with a confirmation that you will need to cross Data Centers to properly join. Click yes, and it goes through that whole process for you before logging you in again on the host's world.
Not a perfect solution, but it's perfectly doable on the infrastructure in-place. Don't try to tell me it's not. Data transfer from Server to Server is no harder than from Client to Server.