This app was mentioned in 7 comments, with an average of 1.86 upvotes
You could try Archos video player. It supports a huge variety of video file types, coupled with a relatively modern interface and easy to use controls. I've been using it for months for the same reason you're looking to switch from MX player and have found it to be a solid option! Better yet, it's free!
https://play.google.com/store/apps/details?id=com.archos.mediacenter.videofree
All the best on your alternative video player searching journey!
A lot of people on here talk about Plex and Kodi. Keep in mind, Plex costs money, and Kodi, while being totally customizable, is also overly complicated for what you want, and in my opinion extremely ugly. Instead I recommend Achos Video Player which simply reads the contents of your NAS drive and automatically sorts the files, names them, and pulls cover art, descriptions, and trailers without any extra steps. You then stream the file from whichever video player you prefer.
I'd suggest Archos Video Player Free or Archos Video Player Paid
Great modern UI and more functionality than you could possibly ask for.
OCH or Torrenting + NAS + Any Android TV + Archos Video
Try archos video player
https://play.google.com/store/apps/details?id=com.archos.mediacenter.videofree