I think that the points about visas are valid but please keep in mind the huge number of expats that live and work in the gulf area/SE Asia that would not need a visa to enter the DR and that might like a little R&R on an island that is proud of its beer.
As far Emirates being an expensive airline it is actually very reasonable and the service is outstanding - while we miss living in the DR moving over to this area of the world was def. an upgrade in the choice of airlines available. I even prefer PIA to American........

Although it takes a while for you to get used to hearing "we will be landing at 8:00.....inshallah" Most North Americans prefer to not rely on fate quite so much.
This route could def. develop in the future in my opinion.