Red Dead Redemption is amazing. If you like GTA you'll like it too. man I was about to recommend getting it at Gamestop since they had been selling it for $5 used forever, but now they jacked the price up to $15. You can get it for $12.89 from the PSN Store right now in digital form. I guess that rise in price for PS3 games is already starting to happen, as The Last of Us was $5 for the longest time (must play PS3 game, though the PS4 version is a lot better thanks to being 60 fps) but is now $10 used at Gamestop. Amazon is great for buying new PS4 games since they often set their price to match the sale prices for Best Buy, Gamestop, the PSN Store, etc, but for used PS3 games I prefer walking into a Gamestop so I can look at the disc before buying.
The only Ratchet & Clank I have played is the PS4 game, which was really good. I do own four different Ratchet & Clank PS3 games, but haven't played them.
I bought them on the PSN Store for like $3 each last year when the PSN Store had all kinds of crazy PS3 deals. Those PSN Store sales for PS3 games have since long dried up though.
If I had to recommend a few awesome late gen PS3 games (eg 2013 or later) that you probably missed, I'd go with
1. Persona 5 (best game on the PS3 IMO)
2. The Last of Us (second best game on the PS3)
3. Bioshock Infinite
4. Odin Sphere Leifhtrasir
5. South Park: The Stick of Truth
6. Metal Gear Solid V Phantom Pain
7. Tomb Raider (2013)
8. Dragon's Crown
9. Guacamelee
South Park The Stick of Truth might be the best licensed game I have ever played. You can tell Trey Parker and Matt Stone were heavily involved in it, as it plays just like a new season of the show. It's short but extremely funny and the battle mechanic is a lot like Super Mario RPG if you ever played that old .