I'm out of my depth with most of the technical stuff about using TVs for gaming (although I can tell you that an end user, like you, doesn't have to pay licensing fees for Dolby Vision and that the number of HDMI ports is irrelevant as long as there are enough for the various devices which you might want to plug into them).
However I can direct you to two well-respected UK websites, which both carry recent summaries of what's best in gaming TVs:
http://www.expertreviews.co.uk/tvs-entertainment/1405345/best-tv-for-gaming-2017-these-4k-hdr-televisions-will-get-the-most-out-of
http://www.techradar.com/news/television/tv/tr-top-10-best-tvs-for-gaming-2015-1289344
Don't get too hung up on the idea that Dolby Vision is the bee's knees in technology though. Samsung's own HDR 10 Plus system is just as highly-rated on many websites (if not higher).