I believe, if you enter a search address and scroll down to the bottom, there is now a "save for Offline use" button. I haven't tried this yet.. https://gigaom.com/2014/05/06/heres-the-button-to-save-google-maps-to-use-offline/
I fail to understand why people think this is a big deal for a device that you set and forget. My Macbook pro on the other hand has an external PS which is a PITA. It would make more sense for a portable device to have a built in PS than a device that never moves.
Airplay is a PITA to use from my iMac to ATV and has lots of issues. I have a late 2103 build iMac and an even more recent ATV and Airport extreme. The imac is hardwired to the ATV via the Airport Extreme. * iMac mouse becomes unresponsive when I enable Airplay* audio fails to play over airplay, I have to restart coreaud daemon* Video is choppy on tv. I can compare with the same video on the iMac screen which isn't choppy. When it works it works OK, when it doesn't (about...
I dunno, nobody is going to sit around for the rumored "Fantastic new" ATV. If I want a streamer box I buy what's best available now. I have an ATV and a Roku I see no need to rush out and buy a new Amazon FireTV or a new ATV. Maybe when one of them craps out I will. Same for new buyers, IMO they will buy best of what is available and stick with it until they "need" a new device.