A lot of the highest rated mods are less about bugs and more the quality of life mods people refer to are usually Sky UI (and Darnified UI for Oblivion). Basically Morrowind was a "PC game" but Oblivion was very consolized (FOV 60, tiny inventory menu with few items visible at once but in huge fonts, etc) that were clearly designed around using an XBox controller + sitting 10ft away from a TV. Any half competent developer would have FOV / UI scaling, etc, in an AAA games's settings, but this is Bethesda we're talking about...

Compare Morrowind UI vs Oblivion UI vs Skyrim UI. Now imagine how all 3 look sitting in front of a nice 32" screen from approx 2.5ft away. Morrowind is gorgeous and shows a lot of useful information at once (eg, all skills side-by-side). Oblivion's inventory though feels like having to read a 10,000 word report written in Size 36 Comic Sans from halfway across the room with binoculars, and Skyrim somewhere in between. Personally I don't usually score games based on 3rd party content, but "If Elder Scrolls games were unmoddable" = I'd probably knock 30% off the score for reasons of sanity... ;-)

Right. Oblivion and Skyrim have bad UI (and character progression, and ...), and reviews of the games should reflect that. If those problems are fixed by user-made mods, that should be reflected in reviews of said mods.

I would argue that Morrowind's character progression is just as bad as Oblivion's, as it has the same issues. (With that said, I *really* like the "skills improve through use" mechanic, and I wish it were more common.)