They need to improve their netcode to facilitate , at the very least, say having 12 servers per logical data center in the EU data center instead of 8 per data center. This is beyond technically feasible (it just requires work, of course) and consistently increasing segmentation of the playerbase could lead to some serious and very possible issues if either the population numbers dont increase or, worse, if they dip. Can further increase phenomena like data centers that are focused and concentrate content like PvP, also hinder static creation overall and on and on . A possible disaster waiting to happen, that is completely possible to be accounted for if the proper measures and work is put towards it.
failing all else there is just about Z E R O reason (and no, "our old bad netcode can't handle it" is not a valid reason) for the game not to have cross logical data center (still keeping physical restrictions) duty finder or even party finder matching. Devs please don't do this.
