They are two different style games. I understand how gta set the bar for open world games and all but they can't even be compared because they weren't made to be like each other.
There are a lot more side missions in watch dogs vs gta. I think I only did the tow truck ones in gta v and well the flight school because it was kind of required.
The side missions are a lie and clones of each other:
- Serial killer final mission: profile and whack like every other random crime.
- Human trafficking final mission: get the guy who has a convoy route like every other convoy side mission.
- Weapons investigation final mission: Survive waves of enemies. Like that other story mission in Act III.
- Fixer missions: 4 different types (as far as I could see) involving you doing pointless driving stuff with the sloppy driving controls for a progress bar and cash you don't need.
- Hacking: Hacking driving where Ubisoft feels like it and only 4 types - bollards, steam pipes, lights, and bridges. And jumping only where are hydraulic lifts. Why does Chicago have all these hydraulic lifts? Coding in jumps would have been too heavy?
I finished the game and some of the side missions but otherwise have forgotten about it. Why would you bother with side missions if they offer you nothing meaningful? As for GTA V this also suffers from one similar issue, the buildings are empty and most you can't even go into or interact with. Its a pretty city with nothing underneath. If you did buy this I'd form a class action and sue Ubisoft. It really is that rubbish.