Honestly, I remember being really disappointed in AC3 when I first played it back in 2012. I remember disliking Connor a lot and finding Colonial America pretty bland.

It's been a decade, and yes Colonial America is probably the blandest setting AC has ever had. But Connor is a good protagonist stuck in a bland story.

Replaying this, I really do like Connor. I think he has a great character arc, but the story Ubi told in 3 doesn't allow him much room to shine.

Unlike Ezio, Connor doesn't really have any Allies that he can play off of. The allies that are in the game are around for a sequence or two and than they're no longer in the story.

Ezio had a ton of recurring characters that allowed you to see who he was outside of his mission.

The gameplay itself is a bit clunky. Neither the frontier or the two cities really allow Connor to show off his free-running skills.

The homestead missions are good. They're short and easy, but help add to Connor's character.

Also, as much as I love Haythem. I feel like the fact that it takes close to 6 sequences to play as adult Connor is also another reason why his story doesn't shine like it should. We get 3 sequences of Haytham. 2 of young Connor, and the young Connor sequences would have been better if they showcased more of Connor's relationship to his tribe rather than being glorified tutorials after already going through the Haythem tutorials.

Overall, I think AC3 is a lot better than I thought it was when I first played it. It's an interesting game, but flawed in its execution.

Also, Daniel Cross deserved a better ending.

Summary: Assassin's Creed III is, at its core, a decent game, flawed by many delusions of grandeur in terms of story choices and size of the open world, which lead to the game's main problem: pacing. However, the combat system is good if not clunky, and the story can get good when it gets going. The remaster is ass on the technical side though.

It's a shame most people will have abandonned this game by the time it gets good. The pacing is completely off in this entry: the first 8 sequences suck, the last 4 are some of the best I've seen so far in an Assassin's Creed game. The main antagonists are great, the game really manages to present everyone in the game (except Connor) as morally grey, really capturing just how grand yet hypocritical the American Revolution was from a civil liberties standpoint.

However, those first 8 sequences are horrid. Firstly, you get your Assassin outfit 6 SEQUENCES INTO THE GAME. You do half an Assassin's Creed game, without being an Assasin. And it's not just that you don't have the (really) cool outfit that sucks, it's the story, the gameplay, everything really. If you took out 4 of the first 6 sequences of the game, the story would remain unchanged. The game doesn't use the extra time it gives to the origins of the villains to flesh their character out or anything, because it needs to hide their "evil side" in order to get the big reveal that you've been a Templar this whole time. So, most of the characterisation comes in the second part of the game where you hunt them down rendering the first half completely useless.
As for the young Connor sequences, the same applies: most of his journey from being a whiney, blindly optimistic teenager to a more nuanced and cynical adult comes from the second part of the game, and gameplay-wise, nothing good come sout of these sequences. But by the end of the game, I actually liked Connor. He got passed his borderline stupid optimism and became more nuanced, without being cynical. I wouldn't be surprised to learn that his character was inspired by someone like President Obama.

The gameplay blows hard. The open world is not interesting, ugly, and, for the frontier and the davenport homestead at least, is empty. The game also loves to make you run from one side of the map to the other just to watch a cutscene, making the size and emptiness of the open world stick out even more, so my tip is to abuse fast travel, you aren't missing anything anyway. The missions can be pretty good and original, but a lot of them are sluggish and uninteresting.
The combat is actually pretty great when it works, but as will be discussed later, the whole game feels sloppy and is quite glitchy, so that hurts what was, in my opinion, a great system that struck a great balance between Brotherhood's overly simplistic but really cool-looking combat system and the other games' grindy combat. Now, enemies will attack you even in the middle of a combo, so you always need to be aware and ready to counter. Also, the animations are great.
The climbing is faster, better, and climbing trees is a cool addition, but nothing amazing to be honest.
As for side content, it's just a worst version of déjà-vu systems. Recruiting assassins was really cool in Brotherhood, but this is the third game to use it, and it doesn't really feel earned story-wise. It doesn't really fit Connor's character to lead a Brotherhood as he's more of a lone wolf. Also, the Davenport Homestead didn't seem very appealing to me, a bit too complex for an Assassin's Creed game (I'm here to split heads open, not resell wood) , so I didn't engage with it but I will salute the effort to not redo the "buy shops" gimmick for a third time.
As for "special" gameplay scenarios, they are enjoyable. The desmond sections are fine, but they are so weirdly placed in the game. The first one comes right after you the assassin's outfit, which is such a pace killer. Putting one in the middle of the first part of the game would've been way better, breaking up the monotonous start to the game. The boat sections are great.

Finally, I want to talk about the "Remastered" part of the title. I never played the original, but even I can tell this is a bad remaster. There is this weird fog that appears so often, the characters faces look really weird sometimes, there a lot of glitches, especially in combat where inputs will be ignored by the game (maybe that's a skill issue). This is a shameless cash grab, that doesn't adress any of the game's issues, which is a shame, because there is a good game somewhere in there.