For those who like this game, have you played Talos Principle? What does this game have over this one? What is it doing that Talos isn't, or vice versa?
I ask because I really dig that, but it's still kind of an obscure game, and Witness has much more hype, so I haven't seen anyone talking about the relative merits of both.
I love both of these games, for reasons that are similar and different.
The big difference is just how organic everything feels in The Witness. The puzzles, how they are integrated into the world, how they impact and are impacted by the world around you, how you learn how to solve them, how you learn more about the world through solving them, and how your experiences on the island shape your interpretation of the puzzles -- it is breathtaking how well these things go hand-in-hand with each other. Yes, this game was in development for a very long time, but it's reflected in how well-designed and thought out everything is.
Whereas Talos is very structured by comparison. The world certainly plays a role in the game's story, but not quite as much from a gameplay standpoint. It has clearly demarcated hub worlds, levels and puzzle chambers. There are occasions where things cross over a bit, but it's not the game's focus. Each level and each individual puzzle within largely feel detached from everything else around it. And whereas puzzle solutions in The Witness are largely governed by your knowledge of one or more rule sets, the limiting factor in Talos are the objects you have to play with in each puzzle chamber.
The puzzles are generally great in both games, even if the execution is different. Talos is much more hands-on, Witness is more observational. In Talos, you have blocks, and lasers, and fans, etc. that you have to manipulate to reach the solution; in The Witness, you're always drawing lines on a panel. But while there's more variety in Talos in terms of how you interact with each puzzle, in The Witness each puzzle plays a part in a much greater whole, and there's a ton of variety here as well in terms of how each puzzle factors into the world.
In the end, I find The Witness to be a more impressive game and a special experience, whereas I'd call Talos Principle a great puzzle game and probably stop there. Obviously I highly recommend both to anyone even remotely interested in puzzle games, whether we're talking about something like Myst or more like Portal. It's awesome and we're very fortunate that these two games exist.