1. The biggest issue I have experienced so far are the Auto Saves. The game isn't auto-saving as it should and often causes loss of progress should you want to return to a recent point. Having to think of manually auto-saving shouldn't be put on the player, the game should do it for you just like it did in Odyssey and Origins.
2. Game Crashes - The game crashes often, and strangely enough around 11pm Central European Time (CET) This has caused hours of lost progression because when the game crashes at this time, it also deletes all auto-saves from a certain point. This can be very very frustrating!
3. When starting a major assault on a castle/fortress, there are battle drums in the background during the fight...a slow rhythmic drum and sticks sound and after the battle you usually return to your settlement to report back that the Shire is now your ally. However, this drum and sticks sound remains after the battle. The only way to get rid of it is to save your game, return to Title Screen and load the game again, or just load the game from a auto-save point.
4. Visual Glitches are constant with screen sheering and jumping at major cut scenes, especially a cut scene shown before a major battle.
5. Visual Glitches causing your character to go underneath the ground..something we would see often in games of the past with poor graphics rendering and coding, but not to be expected today,especially from a AAA Title.
6. Visual Glitches with objects floating in the air, or buried halfway in the ground.
7. Melee isn't polished. Its often choppy and unpredictable. This really needs to be worked on, since this is basically what you do in the game!
8. NPC Dialog - It seems there were basically 2 voice actors used, one male and one female, that very loudly say scream the same things continually. These characters should be given a few more lines for variety, and the volume of the NPC screams turned down. Its very very annoying!
9. Not to be able to change mounts and ship skins in the Menu was a really bad decision and should be added to the game menu selection.
10. Opals for Items - we are given far too few Opals to be able to keep up with the daily and weekly items being offered. Something new added is a daily item that you can purchase with Opals, but you may be saving up for a weekly item you want. This needs to be balanced so that the player can work towards his weekly item objective and yet still be able to take advantage of the daily items being offered.
11. So many abilites, yet so few slots. In Odyssey we could double up on the ability wheels, giving us 16 total abilities at our beckon call....but now currently limited to only 8? In Odyssey I am very familiar with all my 16 abilites I have on my wheels and use them all...this is fun! Being limited to only 8, with so many more that I would like to use, isn't fun! Its down right annoying.

I will add more feedback as I continue to get into the game...these are just my first impressions. I like the game, I love AC, but I have to say that Odyssey was and remains way better. Odyssey was a fine polished game, and the dev team listened to the community after release and continually improved the game to make it really the most polished and interactive AC yet! Its yet to be seen if this different dev team will do the same. It seems I am playing a game in Beta Phase, and not a polished and finished AAA Title. I get it that there will be some bugs here and there, but this release has been plagued with far too many!

Continued:

12. No Mounted Combat - In Origins and Odyssey there is mounted combat, ie being able to attack animals or enemies while on a mount...why is this not in Valhalla? Constantly having to dismount to defend yourself against attacks on the roads is really annoying and especially since it was a feature in the previous games. WHY NO MOUNTED COMBAT?

13 In the Glowecestrescire Quest, there is an NPC with a Question Mark, sells a Map...but when you try and interact with him, nothing happens. There are 2 different of such NPCs haning aournd the same spot, the other you can interact with and purchase a map.

14 Aggro Animals - Ever been chased by an wild boar or other predators for over 500m? 1000m? It seems the devs forgot to put a range on the animals chasing you like in previous games. Another blunder or functioning as intended?

15 Animal Assassination Contracts - So new to Valhalla is that when you perform an assassination or you kill another viking, you then instead of stabbing them again to confirm the kill as in past games, but you put an ax in their hands so they can enter Valhalla. So why does is this ax animation also for Animals?? This makes NO SENSE and should be changed to the stabbing animation to confirm an animal kill.

Its 8pm CET, and my game just crashed AGAIN. Its now been 22 minutes since the last auto-save, so thats 22 minutes of game time now lost.

16 Invisible Fish - After catching a fish, there is an animation where Eivor is holding his catch..but the fish isnt there, and Eivor is just holding his hands out as if here were holding his catch.

17 Runes - There isnt a way to remove runes from equipment or clothing unless you move them from one item to another. We should be able to remove runes from an item.

18 Loadouts - In Odyssey a great feature what that we could have various loadouts, which would make alot of sense for Valhalla for various armor and weapon combinations. We need 5 Load Out Slots the same as we did in Odyssey.

I have completed the main quest line....and upon completion, all FAST TRAVEL points arent working! The fast travel points are grayed out and not functioning. I might as well not even play the game now! I am not going to ride a mount 20 mins long to get to a POI. This is just ridiculous!

19 Bjorn keeps haning aroud my settlement, but I cant recruit him. Recruit is grayed out when I try selecting it. This should be accessible and I should be able to recruit him.

20 Seems to be no possible way to conclude the wedding of the blacksmith. I seem to be stuck and cant get out of the wedding after talking to everyone possible and performing interactions like bobbing for apples, which has a delayed interaction sequence.