If you still want to do DXB, then the other 2 sements will have to be in a 2 class plane as there are no 3 class European routes!
So, why not pick somewhere nice in mainland Europe and do a day trip? If you want to maximise miles, the Canary Islands or Athens spring to mind.
As suggested above, if you are looking for DXB replacement, CAI is a good option as you can buy a visa on arrival. Also consider BAH which is also visa on arrival.