I don't see how this game is hard. Better than SMG2. This game is amazing, but it isn't the same as the first.
Here is how the game is different. The game is one GIANT map. You can drive around in your car which allows you to get around very quickly. The game is huge as I mentioned before and in my opinion was well ahead of its time for a platformer. The thing I love about this game is the exploration. You can go cruising around in you car, and explore everything, and find some cool areas that are there just for the sake of extras. Like you will pull over to this really peaceful area, that is fun to explore, and has some small collectables in it, but that is it. Also the game is broken up into mission quests, and side quests.
Side quests in this game were pretty cool in my opinion. There was a dinosaur section, a giant temple, and many other stuff. The other thing is that this game seemed to have several side storylines going on. There is this one mysterious girl that seems magical, and has some storyline. Also the terrain and landscape in this game is awesome. Especially walking into Sly's domain which is a tower guarded by a giant field.
The storyline may not be too intriguing, but there are a lot of fun and memorable moments in this game. Again the music in this game is awesome as usual, the voice acting is also awesome. And driving the super bunyip was a lot of fun. Also in this game you can upgrade your boomerangs like you firerang to a lavarang, and the upgrades are pretty cool in my opinion.
Boss fights are a bit easier in this game, and require much less thought. Enemies though have gotten a lot larger in number, and are much larger in general. There are many times where you take down collosal walkers, or have to fight armies of Uber frills.
Overall I think this was a great game, but maybe only for fans. I think there is a special group of people who enjoy these kinds of games, and you don't have to be a kid to enjoy it either.