For what you're expecting to do with it, I expect a MacBook Air to work very well. I use a 2012 MacBook Pro (yes, the old, heavy one) and the keyboard and handrest is quite similar. I have loads of colleagues with MacBook Airs as work laptops and they are all very happy with them. The Air is very light, quiet and just works. The handrest is large enough (based on the 13" model) and I would not expect any issues with it. My Pro has a more significant edge due to the thicker body, on the Air the keyboard sloping down to the thin edge will mean that this is hardly noticable when typing. My employer lets us switch to a newer laptop every four years, but I have seen loads of colleagues hang on to their Mac Airs as leaving a four year old Mac Air for a new one just seems superfluous. You'll get the same body, the same performance (the upgrade in specs is hardly noticable for regular office work) and the old one still runs like new. You can get a lot of mileage out of a Mac Air. I would recommend getting one.