I was in a similar situation and upgraded this last month.
My previous was a 64GB iPad 3 Retina Wifi running iOS 8. Everything ran fine, my only gripe was that Safari seemed slow. I had restored the iPad twice since my owning it, so it may have been a fresher install that did the trick.
I replaced it with a 64GB iPad Air 2 Wifi. Everything is really fast and "snappier" as expected. My only gripe is in comparison to my last iPad 3, this iPad feels too thin. That isn't a bad thing, but it takes some getting used to. I also considered the iPad Mini, but decided the Air was better value.
I bought a Zagg Glass Screen Protector. After installing that, it ended up being defective. The tag that says "pull here first" to remove the plastic on the protector left a big square mark on the protector I couldn't buff out. I removed it and sent it back. It's currently in a
Khomo case, but soon to be upgraded to an Apple Smart Case. The Khomo case has a hard plastic rear the Air 2 snaps into. When I removed it from the case to apply the screen protector, I had to be careful because of the iPad Air 2 thinness. When moving it in and out of the case, it's easy to apply pressure and have it show on the display (it's that thin). I think the Smart Case has a more flexible rear portion that would prevent this. I'm also planning on trying the Moshi iVisor protector as that worked great with the iPad 3. It wasn't available until recently otherwise I would have bought that instead. I've never had really good luck with Zagg products except for a whole device protector I installed years ago on a PSP.