Foreword:

The Elder Scrolls IV: Oblivion is the halfway point between Morrowind and Skyrim. It simplified some systems but I still remember it mostly as being the first time in my life I was giddy with excitement as I heard Patrick Stewart's voice in a video game just to be sad the next moment as I realized our chance encounter was too be cut short by the unwavering fates.

Aesthetics:

We start in a prison cell, a chance visit frees us and we are left in one of the best tutorial zones in a game (in my opinion), the Imperial Sewers. The characters are voiced now which in turn makes the conversations shorter compared to Morrowind. Of the main cast, the best character is The Emperor, Jauffre is a worse Caius Cosades, Martin is ok, and Sheogorath is a genius (also part of Shivering Isles, one of the best expansions made by Bethesda). Quest-wise you have a lot of forgettable ones and a few amazing ones like the last Thieves Guild quest or the Dark Brotherhood chain.

'The game has improved considerably visually from Morrowind and the soundtrack is amazing. The voice acting is ok. The game looks and feels good even today.

Functionality:

The game has a multitude of character generation options. It has the same attributes (Strength, Intelligence, Willpower, Agility, Speed, Endurance, Personality, and Luck), races (Altmer, Argonian, Bosmer, Breton, Dunmer, Imperial, etc.) and stats (Health, Magicka, Fatigue and Encumbrance) as Morrowind. Still, it removes skills like Spears or Axes or changes the linked attribute as is the case for hand-to-hand moving from Speed to Strength. Speechcraft and Security have simple minigames that do not outstay their welcome. You also get to pick Birthsigns like in Morrowind, not much has changed.

You have different factions you can join like in Morrowind, except the regional Morag Tong which has been replaced with The Dark Brotherhood.

The combat can be a pain, if you do not level your character properly at very high difficulty and levels you can have a hard time thanks to the level scaling. The spellcasting is very strong, however, especially after you unlock the Arcane University, which will give you spell making access.

The game has quite a few bugs without the unofficial patch, I did not encounter any game-breaking bugs however like the infamous Morrowind Tribunal bug.

Enjoyment:

I loved TESIV: Oblivion, the modding scene was extraordinary and it fixed all my qualms with the game. I remember with joy even the tedious moments like when I blocked my keyboard with a coin to level sneaking or getting pincered by mud crabs as I was leveling my armor skills.

Conclusion:

TESIV: Oblivion is a gem, without mods, it is a great game. With mods, it is a phenomenal game. Even at full price, it is an extraordinary deal.

Other Notes:

None at the moment.

I'm not sure why, but even after years, I occasionally come back. You might call it my personal dream realm. Because when I'm feeling down by the real world, I always come back to Cyrodiil to chill in the woods or hang out at Frostcrag Spire, listening to the Jeremy Souls' masterful soundtrack while I sit with a cup of mint tea in my hand. And you might call it nostalgia, of course, and be absolutely right about it. Because if it wasn't for nostalgia, I probably wouldn't even bother with it. It's just too janky. In comparison to Morrowind and Skyrim, this game is a complete mess. But let me tell you about it in the proper order.

Overall, the gameplay is the most off-putting aspect of the game. It's similar to Skyrim, but with a terrible leveling system that makes the game unplayable at higher levels. When, in order to play normally, you need to cheese in some form. Not leveling up, choosing as your main skills those you won't use, or using mods. You will encounter a huge number of bugs. Some of them can be hilarious, some of them annoying, and some of them can ruin the game. Isn't this a classic Elder Scrolls experience, hm?

Is it really worth it, though? To be honest, the short answer is NO.
Because all this game has to offer are guild quests. Maybe the most interesting guild quests in the entire TES series.
And that's it! That's it; there's nothing else of interest here. Oh, and the dialogue between the NPCs is really something else. That's for sure. 

Oh, and I haven't forgotten about God of Madness, which is exactly why I'm giving this game a positive review. Cheese to everyone, dear ladies and gentlemen!

Buy Starfield so Todd can make a new Elder Scrolls, so you can buy Skyrim again.