Yeah, Arya was my favorite GoT character back when I was into it as well. It really says something about GoT that, despite how dark this series gets at times, it's still a lighthearted romp compared to GoT. At least here Masie's character will get to make friends who won't die.
Cammie's a LOT less violent, at least. It's somewhat ironic: Cammie is a soldier who doesn't really want to kill anyone, while Arya is a princess who spends the first 3 or 4 books becoming an assassin and loving it.