For one, the streaming actually works, that's an immediate win. HDR is also present. Image quality is better at the same bitrate.
But to your other points,
Remote install I was not aware that steam remote play could do, that's a pretty nice feature! Streaming big picture mode and choosing a game to download is easy enough though.
Steam big picture is there by default, and your whole steam library is there. You can add games manually too, but personally I use big picture for my steam library and playnite for everything else. Plus the games that were scanned through GeForce experience were automatically imported, not sure if that'll be the case going forward though. But they do have an import script.
Edit: not sure how it appears to others, on my device it just shows a picture and not the text I input, it's my phone on cellular showing you can connect outside the same LAN.
Does Gemini still fail to do all Google Assistant tasks? Such as reminders, home controls, etc.?
I remember it falling so hard when it first rolled out and I never have it another shot. Is it any better?