Okay, so throw away everything on which they've built a successful business?
And do what to replace it?
Besides making a new Driver game, of course.
Literally Quality over Quantity.
Look at the Unity map
Look at all this crap on the map. and its not even all of it. What is this content? Its mostly collectibles.
Ubisoft needs to find a new loop, and honestly I just say "look at witcher 3". That game genuinely feels like you are discovering content, rather than it all being plastered in such small proximity to one another.
These games need to find their own identity. Far Cry could have been a survival sim properly refining some of FC2's mechanics like what Hutchinson wanted with hypothermia, and air management.
Watch Dogs could have super doubled down on the simulation elements, made guns a frowned upon method of dealing with situations, and instead make hacking your primary method for solving problems. Instead the game is so insecure with what it wants to be, every situation can be solved by shooting. The reputation meter means nothing.
And Assassins creed... just make it a good stealth game. You are close to the people who work on splinter cell. How AC still has these horrible stealth mechanics blows my mind. And just make combat something like how souls does it. Where you and your opponents are evenly matched. You might be able to mow them down, but they can do the same to you. You are so stupidly overpowered in most of these games, but in unity they changed it so far that combat is slow and boring, and you are entering combat so much because their aren't enough stealth tools, and not to mention most of the time, they didn't even work.
There are a lot of things they could do, but they constantly stick to the "climb towers, fill world with stuff"
Make it less stuff, but make it higher quality. Make these games have unique mechanics for each of them rather than the same repeating game loop.