Things 3 is excellent. Any fan of well-designed and well-constructed software will appreciate it.

I also like the philosophy behind Things: make it really easy to add items and make the core workflows fast. Additional complexity (tags, dates, projects) is incremental and optional. It's one of the few GUI apps that can be operated solely from the keyboard with no loss of functionality.

As far as I'm concerned, the only feature that Things lacks is shared lists.