Mediocre story, there might be two interesting characters in the game. Map design for the main missions are very well done.
The open world is decent. Great minigames. Decent environmental puzzles. Decent stealth shooter mechanics. Good immersion, car chases are fun and exciting. This game has a good amount of decent content. Plenty of humor from the modern world. Plenty of collectibles and side missions to keep you busy.
Online modes are very fun but sometimes very frustrating as well. These will keep you busy because the online challenges arrive randomly, and they are fun enough for me to accept every single one.
Great graphics in my own opinion, I never paid for a high performance gaming PC and I have set my own expectations. This means your opinion might differ from mine.
From a fun and content amount perspective, it is very comparable to Assasin's Creed 4 Black Flag, which is another open world 3rd person game.