If you are coming over as a married FO without kids, you will get an apartment-- most likely 3 bedroom and of good standard. If you have kids at home, you will get a villa. Captains will get a villa with or without kids.
You can take the apartment furnished if you would like, or they will give you an allowance to furnish the place (AED30,000 or about US$8000). You will get to ship a couple of hundred pounds of airfreight at EK's expense.
The wife can travel all she wants. The restriction is how much you are willing to spend on the travel.
Good luck.