The Isle - It's in a weird spot with development because there are currently two separate branches on Steam:
1) Legacy: the old version of the game, which is buggy and a little rough around the edges. It's lacking in gameplay but could be fun if you just like running around as a dinosaur.
2) EVRIMA: the in-progress remake of the game. Much more fleshed out mechanics, optimization, etc, but due to it still being developed it's missing a lot of content and there aren't many dinosaurs currently playable. Given that it's in development though you get to see new updates pushed out, which is exciting.
Ark: Survival Evolved - This is a TERRIBLE game from a game design perspective, it's an unbelievably massive game and it's horribly optimized, but heavily modding it can make for a fun experience- fun enough that it's taken the spot of my most played game on Steam, at 750 hours.
Primal Carnage: Extinction - FPS game featuring Dinosaurs vs. Humans. It's old (still runs on UE3 lol) and has a dwindling playerbase but it's honestly a pretty fun game. Lots of different classes/playstyles to choose between, and features decent dinosaur models and animations. Surprisingly is still updated, despite being so old.
Prehistoric Kingdom - Park builder with an extremely high level of detail and control. Excellent animal models and animations with a pretty sizeable animal count. Not a fast paced game, so if you're looking for something slower and more laid back this is a good choice for you.