I simply want to tell people what surprised me about this airport. Unless you go to the smokers' enclosure or cafes/restaurants, there are virtually no seats at all in any of the three terminals. In Terminal 2 there are about 10 metal seats and nothing else anywhere (departures or arrivals, any terminal) but in the smokers' place there are quite a few soft chairs and couches/sofas. Take this into account when deciding how far in advance of departure you will go there. If any of your party finds it difficult to stand for any length of time, don't schedule to go to Madrid airport.
...and the longest walk I have ever had to get to my departure gate. It felt like I'd walked back to the town centre. Leave plenty of time to get toy our gate!