There are really only two ways to take in a game like Crackdown 2. You either love it for being exactly like the first game or hate it for having very little change to the overall formula. I side with the love it opinion because if it isn't broke don't fix it. What Ruffian offers players is a game that doesn't need a critical patch not to be an awful game, it ships as a triple A title.
Surprisingly the story is a bit more focused this go round, mostly told through the audio logs scattered across the city. These provide some insight onto what happened since Crackdown 1 as well as info on what these freaks are. By end game the origin of the freak virus or the game's new enemy the Cell terrorist organization aren't very clear at all. The freaks may have been the very same from the Shai Gen organization in the first game or something else. Like early seasons of LOST you just end up with unanswered questions. The best one can say about the story is the Agency wants to clear out the freaks but the Cell don't want the Agency to do so and feel that you are being played.
It doesn't seem like it at first but the graphics are much improved over the first game. No longer does the game feel like a cheap cell shaded style, objects are smooth and textures do not look blurry. If anything suffers in this department its the actual characters, that are recognizable but don't exactly look great on stairs when they are standing perfectly calm on thin air. It's an extremely minor nitpick but in a generation screaming for realism, Crackdown 2 spits in its face in every way it can.
The audio is the weakest part of the game again. When sound effects become the main effect of your game (See: Anything the Voice of the Agency utters), the background music takes a back seat. In this case limited to car radios like most sandbox titles. Some great tunes can be found in the game but in the 30 hours I put into the game I was never in a car long enough to get anything out of the tunes. The only music in vehicles works for games like Saints Row or Grand Theft Auto as you spend a good chunk of the game driving or flying. With Crackdown focusing on leaping, climbing and gliding their is never a need to be in a vehicle except the helicopter, which of course has no radio.
The mission types only slightly vary with four different types. You either activate a beacon that is minimally guarded, take a tactical stronghold back from Cell which is a bit of a fight, close a freak breach which is easy experience, or deliver a beacon which is a simple guard an object mission. None of this ends up being hard but it is a blast with multiple players, by yourself it's a pretty big drag. The issue with the missions isn't the lack of variety it's more so the enemies. The enemy AI is rather stupid and not a threat even on the hardest difficulty until the very end of the game.
All the freaks in the game are easy kills that pose no threat in reality. They serve as tools to earn achievements and raise your driving skill with easy as you plow them over in mass. The biggest freak in the game has no interest in you only the beacon you try to defend, and the second biggest found in the game's final mission are pushovers. They look menacing and you can give Ruffian credit there but even at the lowest agent level these things are a joke.