Actually if they do anything it should be:
Offer players on DG/MDN the choice of going to Dalborra or back to a West Coast US PVP/RP server. Some people care more about latency, some care more about RP/PVP. One solution does not fit all so you give people a choice.
That said: I'm on Dalborra so I'm all for boosting our population but I don't suffer any of the downsides of a server transfer. I feel for the people on GD/MDN though.
Optional transfers makes the population situation even worse for those people who want to stick around. Look what happened to the origin servers after they first opened transfers.