Good picture quality & resolution (e.g. LG panel), no (or replaceable) smart features, no forced ads / tracking, fast startup, wide variety of inputs would be bonus though the usual options are fine.
I'm less imaginative around would-be-cool features. If there was an integrated, hackable linux computer you could do many more things like photo frame, weather, (privacy respecting) smart home controls, media server, etc.
I have a TV that takes a few seconds to boot to a screen that says I need to agree to some demands in order to see advertisements. Fortunately, there has yet to be a software update that's so heavy-handed that I can't use the built-in chromecast without agreeing to their demands.
I am really rather glad it was a gift so I won't feel bad trashing it when the time comes. It makes me appreciate how nice a dumb TV is when it's connected to a smart computer and also how important it is to provide the computer myself.
I agree that the smart features are bad, but it's at least still easy to just avoid them. Although I'll admit to not having a great solution to input/control. I currently just use a wireless mouse and keyboard, but that's less than optimal in a living room situation.
I don’t think they sell them in North America though.
It’s all the things you want: has no ads anywhere, turns on in a couple seconds from standby, has a great image (they say it’s used in Hollywood for color grading or something), the “smart” is very light if you care to use it (I don’t and it doesn’t get in the way), is fully supported in home assistant… It’s basically a damn good screen to show whatever I want to see. It’s the polar opposite of the dumpster fire that Samsung TVs are for example.