The bulls are a team that literalyl needed just one piece, a shooting, scoring perimeter player (Rip Hamilton) and I thought they immediately became a contender. Well they got Rasual Butler. Im not sure that makes the difference.
This team reminds me offensively of the Lebron Cavs. Their offense is easier to stop because it is rather predictable. That being said they do have more talent around Rose than LeBron had.
Also, their defense is just beastly...much better than anything Cleveland had.
While I agree with the OP that Chicago's offense can struggle at times, their defense doesnt. With Noah back now, its even better and more versatile.