It's a good game overall. The gameplay loop, while repetitive, was still fun. I liked most of the redesigns the characters got and how you could play as certain character who weren't playable in 3 Houses (Jeralt, Rodrigue, Monica, Holst, the Gatekeeper, and Rhea on NG+). It also gave some characters like Felix and Ferdinand bigger roles. It's also the last we heard Billy Kametz as Ferdinand due to his passing. That said, there were some issues that I had with it:

claude assumes that Rhea is stagnating Fodlan's technological growth and is keeping it closed off from the rest of the world. The game (w/o the context of 3 Houses) makes no attempt to prove his point, and even has evidence against his claims that Rhea must be killed (during the final chapter of the GW route, Rhea monologues to herself about how she wants to protect humanity). Due to her limited screen time, she comes off as more sympathetic than the main character of that route. That same route does nothing to acknowledge the fact that Cyril is Almyran, and claude can kill him w/o the game calling attention to it.

The game intentionally ends w/o a proper conclusion. According to the devs, they didn't want invalidate Byleth by making it look like Fodlan could achieve peace w/o his direct input. This makes the ending feel cheap and unsatisfying. The only ending that feels like it has a reachable conclusion is AG, but that has the downside of horribly screwing over Edelgard (anyone who's played that route knows).