I remember playing TES 3 on Xbox One for the first time. Wow. Even PC modded Oblivion never quite made up for all the raw and awesome beauty of that game and world. Since then, I've played it modded on the PC in two separate installs with different mods at the time and they both looked great. I've not played Morroblivion - if its missing anything from the original then that would be a bit of a game breaker for me although I'd probably try it just to try it. Still, if I had to pick only one then I would go with tricking out the original game. Using a later engine might be good for some games, but Morrowind is rather special.