TL;DR I am very satisfied with this game as an old Sonic fan. Long gone is my shattered heart from the unforgettable Sonic Forces hype...

The Open Zone kills it. Admittedly, its design with random platforms, rails, bumpers and dash panels isn't the greatest but what saves it is the sense of exploration you get from each island. The challenges that unlock the map are piss easy but that doesn't make them annoying. They are bite sized, small distractions from all the running and jumping around. The physics are great and the drop dash from Sonic Mania is in a 3D Sonic game for the first time! You can get some amazing momentum rolling down hills and can gain lots of height jumping after boosting on an incline or a rail.

Cyber Space... Bad physics. Most of the levels are bad. The ones that copy their level designs from SA1, SA2 and Unleashed are very fun. But yeah... The physics are bad. You can fix them with mods but they break some stuff with the game, so I do not recommend doing that.

There are some stupid mini-games in the main story quests. Sheep herding... And the worst: On the 3rd island, there's a bridge you cannot jump across, there's an invisible wall. Later on in the story, Sonic jumps through the bridge in a cutscene while jumping TO SPACE. And you have to get him to the ground IN A TIME LIMIT. I hate arbitrary time-limits. Stupid mini-games like these should NOT exist in the main story.

Elder Koco leveling takes way too long, just like Hestu from BOTW. I spent an hour pressing menu buttons and waiting through unskippable animations and text just to get my speed and ring capacity to the max level. Hermit Koco is better, he just levels your ATK and DEF at the same time while using all your resources. Why doesn't this also exist for Elder Koco? I have no idea.

The final boss, even the true one which you only get if you play on Hard mode, is a joke. The true final boss comes out of nowhere and is a very, very big disappointment. Regular bosses in this game are more like the final bosses you'd expect from Sonic games.

Better get ready for some Ikaruga

The narrative. Oh the narrative. God bless you Ian Flynn. We finally have a serious and comprehensive Sonic story after years of junk and especially after the disappointment that was Sonic Forces, I am very happy with this one. Expect callbacks, direct references and actual story connections to ALL past Sonic media, including but not limited to Sonic 3, Sonic Adventure 1 and Sonic Adventure 2. The dialogues and writing are also amazing, Flynn definitely knows how to write the characters and playfully dances around their personalities, thoughts and dreams. There are some unexplained stuff in the game which I think they are saving for a future title. We'll see.

This is a weird one. While the game looks outstanding there is an insane amount of pop-in and you have no way to fix it. There are 30 and 60 FPS caps for the game and while you can unlock the framerate using Cheat Engine, it breaks certain aspects of the game, so I do not recommend doing that at all. All cutscenes are locked at 30 FPS. Besides the pop-in everything looks gorgeous at High settings. I cannot comment on the Low settings but I'd assume it'd look similar to the Switch version, which I find very ugly. I don't think the game is very demanding at High settings, as long as you have a decent system you shouldn't have any issues running it at 1080p 60 FPS.

I still don't like Roger's Sonic voice, even with this serious direction but many of the voice actors do a great job. They fit the tone of the game perfectly while not feeling too forced or cheesy. And while I don't like Roger as Sonic at all, I can't really imagine this story with Jason's voice either... But it is what it is. He does a great job and improves throughout the game. He starts sounding better as the game progresses, so maybe there were some issues when recording for the game first started.

The Open Zone musics are amazing. Some Cyber Space tracks are amazing. Most are subpar and forgettable. Boss musics are epic, except, again, the final boss. I have no idea why they thought that final boss was a good idea.

In my opinion, this is an amazing step in the right direction for Sonic. I finished it 100% in 26.5 hours without rushing. I hope they try at least one more game with this formula and improve upon it. Even zooming around the Open Zone mindlessly is fun, movement is fluid, it's just great. Very excited for the future.