Absolutely an improvement in many ways since the first game but has many downsides as well, just as every game. It is better than Evolution 1 when it first came out, but better than current Evo 1...? No. But just like the first game I'm sure they will add more content and features as the game goes on, and of course after Jurassic world Dominion comes out.
Here are the upsides and downsides...
Upsides:
1. Better graphics.
2. Better physics
3. More dinosaur variety, over 73 species
4. More creative possibility through decor
5. More gamemodes.
6. Auquatic and Ariel species
Downsides:
1. Short campaign(though the second part will release with dominion to avoid spoilers)
2. Horrible sandbox mode. Can't play in any of the campaign maps, (yet)
3. Chaos theory is an overall disappointment. Had way more potential.
4. Guest physics remain the same. (Still walk through doors.)
5. Harder to get everything unlocked for sandbox mode
In my personal opinion I would rate this game a 7 out of 10 FOR NOW. but I'm sure that rating will increase over time as they add better features and fix current issues.