There are obviously several things Oblivion has done better than Skyrim. We can all see that. But can we just simply conclude that Oblivion is downright better than Skyrim? You can have that opinion, in the same way people (like me) can disagree with that.
Of the things you listed, I'll agree with UI. Yes, only UI.
-Quests
Quests what? Style of quests? Duration? Scope?
I personally believe that Oblivion did the Faction quests a lot better, both in quantity and in quality. I can't speak for the Main Q as I haven't even started it yet, but aside from that I don't see any glaring difference with Oblivion. Quests are still largely fetch&kill, it's just more obvious due to the lack of a journal. Why that? The journal adds a story element to the most mundane quests in Oblivion. Skyrim gives us a grocery list, effectively framing these quests as 'Do X, Kill Y, go to Z'.
-Magic
Personally, I like the current magic system. It works, it looks incredibly good and it added dual casting. It allows us to hold a spell in one hand, and a weapon in the other, effectively fulfilling the dream of many Battlemagi. Magic is not affected by simple armor rating, which finally makes sense in Skyrim.
It lacks spellmaking. Yes. I for one never used spellmaking, was never compelled to use it and never felt that I was gimping myself by not using it. Ok, Mysticism has been removed, but it has been redistributed. Some spells were removed, those can and are easily added through mods.
Ok, if you value spellmaking this much, I can understand your point. But I disagree.
-NPCs
NPCs what? They are voiced better than before. They look better than before, they are more diverse and (to me) more believable. They interact with the world in a better way too. Are they robotic? I don't have this feeling. This is Skyrim, I find their solitary, distant disposition fitting.
-Skills
Skills are still present as perks. Ok, not all of them, but they removed the chore of Major and Minor skills, of selecting certain skills as your major skills so you could control your leveling and avoid leveling up far too quickly.
The current system is far more logical: Using every skill progresses you towards your level up. They also added the, in my opinion, incredibly fun perk system. It adds a dimension to planning your character, it adds to the experience by visualizing your progression, and by making clear what you can expect when you level up.
-Hotkeys
I’ll let this one slide. Hotkeys works just as well.
-Armor
Pure personal taste here. Armors look great in Skyrim, there’s enough diversity. It’s not better or worse than anything Oblivion featured.
-Creatures
How? Because we’re no longer seeing Imp after Imp after Imp? There have been numerous great additions to the creature base in this game. Perhaps you dislike them, fine.