Maybe it's gotten better since they first dropped, but this article alludes to the storage limitations. I ran into the problem with mine. I remember I had to delete apps and clear app data to get enough space to install an update.
The article also speculates the lack of storage may be why they Android version hasn't been updated on them since release.
Sorry but I'm not sure I understand you. I haven't had mine on in a while (got a Roku) but I recall that there were apps for all the major streaming services.
Not directly related, but if you ever want to watch YouTube videos on a Chromecast (or any Android TV-based device), check out SmartTube. It completely removes all ads and other annoying stuff and massively improves the experience.
More storage and AV1 hardware support are the most obvious things they could add. Personally I just want smooth, non-laggy UI navigation. Hopefully performance will increase just by virtue of it being a newer chip.
Something I have been thinking a lot about lately when it comes to Googles products, especially the Chromecast since they started shoving it so full of ads with their Google TV launcher.
Most of the flexibility I like about Android TV over say tvOS is that it allows me to customize things like the launcher or use SmartTube over the official YouTube app. The thing is the only time I care to do such things is to get away from the mess Google made of the product or service, usually with ads, to begin with.
So it becomes this circle of I prefer it only because it lets me undo things that it pushed upon me that its competition doesn't in the first place.
Long winded way of saying I'm not real sure what Google could do with the new model that would make it compelling to me beyond a bottom of the barrel product for a guest room or something, and even then the Onn 4k is cheaper and more or less the same experience, over just replacing it with an Apple TV when the time comes.
Apple TV doesn't allow any customisation at all, Android is definitely the lesser of two evils with smart TVs. But really just get an external monitor connected over something like DisplayPort, running whatever OS your computer runs, for much more flexibility. There's no need for a TV to be running its own OS, and it usually just makes things more complicated.
I didn't even realize how repulsed I am by Google until I saw this. I don't have any interest in putting another data collection device in my home, especially not one that I don't have control over.