Lots of suggestions but from my experience id say go as cheap as possible. Even the best electronics these days are designed to be disposable.
When I was TV shopping, I got wrapped up in the specs until I really thought about my intended use. I stream everything... everything. 4K and HDR are nice but the majority of the time it's not going to used to it's potential.
I have a $400 55" Toshiba LED and a $200 39" Vizio and they will serve my needs until Google Fiber rolls into town.
I wouldn't cheap out on buying a 4K tv if you are going to be using it for home theater enjoyment. Yes watching basic cable sucks on it (it sucked on a 1080p tv too), but I buy and watch blu rays/4k blu rays. If you are going to be purchasing and watching 4k movies, make sure you buy a tv that supports both HDR10 and Dolby Vision.