Sorry to see you leave, hopefully you will join the pity party next year. That being said, EK has more connection options than EY. And DXB is hands down a better airport in the region than most, even if we discount the lounges. Airline pricing strategies are a strange animal, run by the revenue management department, £480 is a great deal and more may come.
[...]Maybe Emirates will be pleased to see the back of me ;-)[...]
Not really they dont give a toss like most businesses, but am confident that they will miss your revenue eventually. Go with what suits you, and come back soon. Have a safe trip