I checked out the Maroo cases and they are very good looking but they state that they do not have the auto off/on cover for now. Hopefully they will and I was also unable to finid weight on their page, maybe the
Amazon page gives specs. Budmonster, not sure what you mean by "second mic"--maybe dock port??--but STM Grip 2 has accessiblity to all ports and buttons. I bought based on a friend who has the original Grip for her Mini and likes it. We've both been through a bunch of cases over the years and decided we wanted light, basic (no keyboards, etc), stable viewing and reasonable protection, Everyone has their own criteria but since the Air is so light, that was one thing that i wanted to maintain.
Lots of ipad Air cases being made available for the holidays so I don't think there will be any shortage of cases now. Just as always though, the majority of them in my area and probably most areas except the largest cities, will be by online shopping though so reviews of those people buy and like is still a good idea.