I don't need to tell anyone how amazing this game looks, every will tell you and show it to you. The visuals are clearly where the most work went.
More in the middle is the design of the game it self, it's generic, it does stuff you have seen a million times, but it does them very well and you never feel frustrated by either controls or tasks. For reference, Astro's playroom is much more fleshed out with new and fun ways to play, it game feels closer in term of design to something like Mario Odyssey but only has a fraction of the content and completely lacks that cinematic feel Ratchet has.
The bad part, and there is one, Ratchet is quite bugged and unpolished in terms of collisions, you can easily get stuck in locations, on crates, objects and other environments. And the solution applied it auto-death to unstuck you. This is rather unforgivable considering much of the locations you get stuck in a very angular and simple, like a bunch of crates. and in one case this issue led to my game completely freezing needing to reboot my system. Thankfully, this is something avoidable as you learn how to avoid the most likely areas where you can get stuck, it's just that easy to identify them.
It is still possible that, by the time you read this, the issues get ironed out through patches, and these kind of problems are usually the easier ones to fix. 4/5, what is done well in this game is completely worth seeing and playing.