Yeah overall I like the new app router a lot. The pages structure was a mess.

It definitely could be better. They're making a pathing mess with eg. parallel routes but it's not /that/ big of a deal all in all. The problem being that when you rely on file paths for routing, you then end up having to build in all kinds of hacks and conventions in the file paths, which are just... not designed for that, they're just keys to files.

But the core of the structure and architecture is sound.