You can usually get up to 21 days in a row of vacation and a few days off on either side as well, so approx 25 days off in a row.
They will usually assign 2 days off on either side of your vacation, and you can bid for more, but the problem is that by the time you find out if you got the days or not, you've already had to book your confirmed leave ticket so you either have to assume you'll get the days and book it or assume you won't get them and book it for 2 days before your vacation starts and deal with what you actually get when your sked comes out.
Wife and kids get unlimited travel, parents get 2 tickets a year on EK (one confirmed, the other standby) but unlimited z fares on other carriers that allow parents. Parents inlaw and immediate siblings are entitled to 2 tickets/year as well.
As for buddy passes they have something called wider eligibility tickets that they make available on some routes at certain times of the year that friends may be eligible for, but rarely on the routes you need at the time you want, so effectively no buddy passes.
That about covers it i think, the pass system isn't bad compared to some airlines, and alot worse compared to others. The major issue being here that all the damn flights are full making it really tough getting on standby unless you are pretty flexible with times/dates.