Curious if you tried static addresses on the Apple clients? I don't see any problem with our Apple clients here, but if I saw what you described, I'd be trying static addresses. And I don't have a Nest thermostat, just an old-fashioned programmable one that we end up setting manually due to have unpredictable schedules. The Orbi is working really well for us, and our guests also don't have any problem with it. We have 4 Apple devices, 2 phones and 2 tablets, plus a bunch of computers, printers, TV's, etc. Everything is working well with the Orbi, and great wireless throughout the house. Sorry that it didn't work out for you.
Oh yeah, I did have one problem with it, the channel on the 2.4GHz. band wanted to be 40MHz. wide, and I didn't like that. I put up with it for a while, and finally just turned off the 2.4GHz. band. That wasn't a functional problem, just my personal preference...I only had one device on the 2.4GHz. band, a wi-fi printer, so I just connected the printer with a cable and called it a day. I could also have used a 5GHz. wireless bridge, but a wire was simpler *smile*.
I don't feel that Netgear rushed to market any more than anyone else. All the router companies (and computer companies and mobile device companies, etc.) want to make money on new products as soon as they can, so they don't leave things sitting around on shelves, they get them out on the market. The ones that really rushed to market that jump out in my mind are the "mu-mimo" routers where mu-mimo wasn't even activated yet. Or the "open source ready" routers that had no open source projects going, or even open source drivers ready to hand off to third-party firmware writers. Of course, I didn't rush out and buy the Orbi as soon as it came on the market. I waited and read reviews, and decided I'd wait for a sale. Finally came along, and the Orbi was functional for me from the first day that I had it.
I guess that not everything works out for everyone. Glad that you found something that works for you, too, though. The Orbi here has been up with no problems for going on a month now. Last time I took it down was to try new firmware for the R7800, and it had been up for about a month before that.
MoCA 2.0 should be fine for you, as long as you're not using satellite TV...I suspect that it might be difficult working around the frequencies that satellite TV takes up...that was an issue for MoCA 1.1, and I'm sure that MoCA 2.0 requires more frequency bandwith than 1.1 did. I used MoCA 1.1 before we got faster internet download speed, and it was pretty much turnkey, very easy to set up. Worked well, consistent speed. Much better than powerline for me around here.