Sally - I will try to answer them completely and honestly.
Leave - it is difficult to get blocks off during any of the school holidays since, surprise, they are popular dates. Peak leave (defined as July/Aug and Christmas Break) should be obtainable every second year. You will only get ONE of the 2 periods not both. So year 1 you will have no peak leave and possibly get a block over the kids school holiday (though don't count on it). Year 2, theoretically, you should be able to get summer or Christmas leave. For some reason, it does not always work and I know people who have gone 2 years or more without peak leave.
Personally, this is a HUGE pet peave of mine. We work like dogs and then can't even get time off to do even small family trips. When the kids are really young you can pull them out of school but beyond about the age of 9 or 10 that becomes impossible.
School Fees - most schools are in the 70,000 dhm/year range. You will pay 10% of the fee/child up to the max (which I believe is in the mid 60's at the moment) and then the entire amount beyond that. Children under 4 are not paid for at all which may be an issue in some schools where there are waiting lists and you lose your spot if waiting till age 5.
Transport is now rolled into school fees so if you schools fees are below the cap transport (bus from a certified company only) will be covered up to that cap.
SO, go look at the school fees online, check out EK's exact max coverage, and figure out how much you will pay extra for your family.
Command - if the captains leaving continues to increase they will find the DEC's they need or bring back the accelerated command. If you are an FO with no jet command I would count on not less than 7 years till command. We have just shy of 4000 pilots. That will need to double for you to upgrade!! Less any attrition. If you come here expecting less you may well be in for severe disappointment.
Travel-- like most airlines this benefit is up and down. First class and biz class travel is nice and I am appreciative of the fact that we can sometimes enjoy it!! If you can get the time off and the loads allow, traveling in a premium cabin with your family is a FANTASTIC perk.
Loads are high though during peak periods (school holidays) so you have to be prepared to pay full fare or get caught out. For family, if they are retired and can miss a few flights there should be no issue.
Unfortunately, with the lack of leave, lack of leave when I can use it and heavy loads we can't really vacation that much. One trip per year is all we can usually arrange. Or the odd weekend getaway.
You know the first year pay. You can easily calculate school costs based on your family. If you track your families expenditures now, especially food, you can online with your wife and looks at Spinnys, Carrefour or any of the online delivery companies and calculate your families food costs.
An FO takes home roughly 22,000 dhms/month when flying. A family of 4 food costs will be a minimum of 5000 dhms a month. School activities, sports etc are all extra costs and not cheap at all!! Set up costs after the move mean the first year will not save a penny. After that it will be very tight. Several friends who are FO's - one manages to save about 4000dms/month but they live within their means and are careful. The other all say they don't save anywhere near that.
It is all very personal. Seen many wives (and pilots to be fair) come here buy TWO new vehicles, big screen TV's etc. and start living the high life expat lifestyle. Reality sets in a year or two later when income just matches payments, there is no money being saved, no money for island getaways.....................
You have all the info you need to sit down with your wife and calculate your living costs here. Just do it carefully and be honest. Make sure you BOTH have the same expectations on the move here!! Heard a few wives comment that their husbands made them move here so they expected the 'nice' things in live to be fully provided.