I agree with OpticNerve except for a few things. I think Kassandra is still my favorite AC protagonist. Her looks (and I don't mean "DAIMN SHE HOT") and her voice acting were just phenomenal. She also had more depth than Eivor. The story of Eivor starts out really good, with a great intro part gameplay part cutscene, but it stops at it's most crucial moment due to some Atimus glitch. I'm sure this is done for a reason but what we're left with (at least I still am, 25 hours in) is a husk of a protagonist; someone who apparently has something happened to them, some important history that made them who they are, but it hasn't been told yet. It also took me a while to come to terms with the fact that this PILLAGING VIKING MONSTER in everything you do, is written as a soft-hearted poet. So don't expect to play as Ragnar Lodbrok.
As for the combat, I think it's awesome but somehow easier than Odyssey. Odyssey's combat felt a bit slower paced, yet fluid with clear animations, giving you complete control over everything Kassandra did. In Valhalla, the animations are more twitchy, like Eivor is moving with muscles that can spring like those of a cheetah. There are a lot of moments during battle that you can execute and "stomp" enemies. This is nice, but it's also what makes the combat too easy for me: you see, every time you get into an executing animation, you are invincible. I think the combat would've been way better and more balanced (and realistic) if you could still get hit during the executes. I'd refrain from executing in the middle of combat in that way, giving the combat feel a better flow and removing the "catching a breath" exploit.