>>716098298
4 isn't... THAT bad but it's just not the same without Dev's art

>>713695592
All the pieces are in place for Sly 3 to have been as great as 2, it just really needed an extra year or so of development time to iron everything out.
>give Dr. M more of a presence: he's the main villain and important to Sly's family history but weirdly absent for most of the game
>change the opening level to Sly and Bentley botching a two-man heist on Kaine Island and realizing that they'll need way more help to deal with Dr. M's bullshit. Alternatively, have them break into the prison where McSweeney is being held and follow up with the first Kaine Island visit
>make the villains connected to Dr. M somehow: I like that Murray and the new recruits have their own problems to deal with and that independent threats make the world feel bigger, but a unified threat like the Fiendish Five and Klaww Gang is more satisfying to handle
>give the Panda King and Dimitri more to do, and give the Panda King a full-fledged Flame Fu moveset to compliment his fireworks
>rework the Guru and Penelope's missions so they feel less like reskinned Murray and Bentley missions: the Guru being a mystic with cool magical and psychic powers has loads of potential for fun scenarios in particular
>give Australia a proper villain, or give the Mask of Dark Earth an actual personality and powers beyond "make things evil and BIG"
>bring back Clue Bottles, treasure runs, and recon missions before starting a new chapter in earnest
I could make more suggestions but this is all just off the top of my head.