EY or EK? Depends on whether you are a Capt, FO, with family or not, love Dubai with all its excitement (and traffic), love Abu Dhabi and its slower pace.
An optimist that EY will improve housing soon or not a believer.
Enjoy being in the big machinery of EK or in the fledgling EY that you can help grow. ie; seniority 1700 or 370.
It's a very personal thing and I know folks at both carriers who KNOW they made the right choice. I KNOW I DID!