The virtual reality business and split screen doesn't interest me much. The new notifications where I can deal with a notification right from the notification is nice. I did a factory restore a few days ago and was surprised at how quick it was. It was the lengthy "optimizing applications" that was missing. I only have 60 apps but the optimizing apps was still a lengthy process. Screen zoom is great. I have it sat to largest so I can see things better, I'm old, and I also have the font set to largest. Being able to adjust the font size and screen size to suit you is very nice.
I usually charge my phone before I got to bed and turn the phone off with the battery at 100%. When I get up in the morning it's still at 100%. Up to Android 6, the phone would lose some juice overnight with the phone "off". When I start up in the morning the device boots noticeably quicker. Mine is around 30 seconds. Not that I'm in a big hurry.
I like Android 7 and the beta version is running fairly well for me. When I first switched to beta 3 my Kindle app didn't work well but within two days it had updated and was working okay. My other apps worked fine. I've downloaded a couple of new apps, mostly dealing with photos, that don't work but that isn't critical at this point.
Thanks for the link. The profile guided JIT / AOT compilation sound great but I'm not sure what they are. Faster operation and less memory used has to be good, though.