Between work and personally enjoying travel I spent A LOT of time at the Calgary Airport and they've made a lot of great changes over the past few years as they grow which makes it a more pleasant visit each time.
They just opened the new international terminal which is a great addition, it's so shiny and new. The customs counter is much better as well, you first go through a kiosk and then get a printed out sheet with a number on it where you are either then free to go or you have to go see a customs agent (someone is there to tell you which one). I also noticed great new art in the exit area and they have greatly improved the baggage area for international. I'm excited to see the new food offerings that are going to be coming in once they open.
Domestic flights have pretty standard food offerings but you can get your coffee, snack and a quick bite. I've eaten at that Chili's quite a few times and the staff is helpful, friendly and lets you loiter a bit when you're done and just working or checking emails with no complaints which I appreciate.
I do wish there was a train to the airport but that's more of a city issue than an airport thing, they have multiple parking options, a bus route, cabs, and even car2go parking if you're a member.