Well finally finished the game so I will post some of my impressions, this definitely feels like a step in the right direction, but still there are a lot of problems.
The story - Not good at all, it starts bad, then gets decent in the middle, then gets pretty awful by the end. Bayek is a fine character, probably the best since Ezio, but all the surrounding cast is barely present or notable at best and the big historical characters are completely wasted. This was the game that was supposed to show the origins of the Assassins and unfortunately most of the scenes relating to that fall flat. One in particular
. The villains are really weak, the last couple of ones are barely introduced and the ultimate villain is one of the least fleshed out villains in the AC series. Even the twirly mustache dude from Syndicate was better.
The modern day story - Just abysmal, the characters are awful, the voice acting is awful, the writing is awful ("Why so aggro?"), the plotline is awful. I was always the one to defend the need for modern day segments in Assassin's Creed games, but after four games of nothing but disappointment I would be willing to let them just cut it. Either actually commit to this modern day stuff or don't do it at all.
The sidequests - Probably one of the most improved aspects of the game, this is definitely where the influence of the Witcher can be felt the most and it is cool that there is more story and more connected sidequests than before,
however, this is where the fact that Assassin's Creed is now a weird hybrid of Action RPG hurts the most. The sidequest objectives are incredibly repetitive, the amount of follow/escort missions is crazy. The fact that there are no dialogue options really hurts the game in this area, since every time there might be something unique and interesting that might happen, like say Bayek going to a party it will ultimately be interrupted and you will be sent into a combat scenario,
Again.
The world - There is no doubt that the world looks amazing, though the lack of Luxor is a really big shame. However while the game shines on the art side, the rest of the game lacks in history/world lore in almost every facet. The fact that every time you finish a tomb you are rewarded with nothing but "Ancient Tablet, From the Old Kingdom" is crazy. Like come on, at least put a myth from Egypt there or the story of the exploits of the Pharaoh the tomb belonged to. There is also no database at all. Now maybe that is all being saved for the tour mode that will launch next year but it is still really disappointing.
The combat - Definitely better than what we had before, but can still be rather clumsy. Now while the combat can definitely be tightened up there is an aspect of it that I am not sure will fit well with the AC games. This sort of combat relies a lot on preset areas and allowing the enemy full control of its surroundings, however since AC games feature freeclimbing and running this creates a lot of problems that I am not sure can be solved easily. Numerous times I had enemies climb a roof then climb down then climb up again for no reason, they just get confused by the geometry.
The music - It is ok, there are some good tracks, but in a year of amazing OSTs this one is nothing special, the fact that at one point it also references Jespyr Kyd's famous score for Assassin's Creed also unfortunately shows that this OST is still no match for his stuff.
The loot system - strange, very strange. It seems like it is only vital early on, and by the time you hit your stride in the game you will be drowning in various items. The tools are also overpowered so you will rely on your weapons even less than you normally would. It also seems strange that armor/outfit has no impact on your character. There are some cool weapon designs and more variety at least, so I guess ultimately it is a positive in that regard.
Ultimately, I am happy that they definitely tried some new things in this game and most of that stuff is an improvement over the old stuff, however in a year with a game like BOTW which also did something similar it just doesn't seem quite enough. Hopefully they finally nail it in the next game and for the love of god get some good writers / or let the writers do something with the overall story.