Morrowind is one of my favorite games of all time. Imo, Oblivion needs it more. It's ugly and the leveling makes it damn near unplayable (for me at least).
Oblivion is by far the ugliest of them. I was going to write about how the leveling system in it isn't that bad, but if you mean the level scaling of enemies then yeah that sucks.
The leveling system was the problem, if you understood it then the level scaling wasn't a problem. If you didn't understand how to level effectively the scaling had brutal difficulty jumps.
The level scaling is still a problem when it comes to item rewards that also scaled. That led to waiting to finish quests until later, or receiving a reward that quickly becomes obsolete.
Yeah im currently playing theough modded morrowind and all of my mods are exclusively textures, meshes, tamriel rubuilt and skyrim home of the nords. And the game still runs and feels decent save the occasional getting stuck in or on random shit, mind you im playing as a Nord (the largest race) and I can do that in fallout 4 and skyrim so who cares.