So I've been to a few NHL arenas, and overall Gila River Arena is pretty solid. It has great sight lines no matter if you are on the glass or at the top of the 200 level. The concourses are nice and big and there's a large selection of (overpriced) food and beer options!
The area surrounding the arena is fairly nice as well with plenty of restaurants to eat at before/after the game.
Only "issue" with the arena is that it's in Glendale. If you're like me and live in the East Valley, it's at least a 40-minute drive out to Gila River Arena. Even though the drive can suck, over all the experience once in the arena is great!