Need a new TV. Any tips or advice would be appreciated!

[rexcrk]

So I purchased my TV back in early 2017 and it needs to be replaced. A line going across the entire screen just appeared and everything above the line is fuzzy. At first I thought it was just on the Hulu app that I happened to be watching at the time, but I see it with every app and video mode.

This is the model I have: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

It's alright, but I think I bought it too hastily. My main concern at the time was getting a 3D TV and this was the ONLY 3D TV sold by a first party at the time (if I remember right), and I considered it having 4K to be a bonus. Funnily enough, I actually didn't like watching 3D at home, because it gave me a headache and that "seasick" feeling, so I'm not looking to replace the 3D (I'd be shit out of luck anyway lol).

I don't know if I just never quite figured out the calibration or what, but I felt like that TV just didn't display 4K as well as I was expecting it to. Bright / outdoors scenes looked amazing, but anything dark just looked washed out for the most part. Not to mention, my TV had a really bad "dirty screen effect"- there was a nice 4-inch block that went across the entire screen, among other bits too. The worst part was that that had looked its worst while watching a 4K disc, so what's the point of having a 4K-capable TV if I can't even enjoy it? I had been going back and forth on replacing it soon anyway, despite just trying to "deal with" the dirty screen effect, but this new horizontal line is something I can't just ignore.

So anyway, this time I want to do it right, since I'm not trying to rush myself into getting a certain feature like 3D or anything. I would love any tips or suggestions or anything (or even to be pointed in the right direction) of what kind of specs I should look for in a TV.
Thanks!