I found it disappointing as well.
Much potentional reduced to cheap gimmicks. While some were funny, others weren't. While you could be all serious in the previous game with the option to go crazy naked with rocket laucher, SR3 makes it the norm, as if it is expected rather than a privilege.
The characters from the previous game have lost most of their personality. Gat gone, Shaundi completely changed and new characters with barely enough time to meet and greet. I would of loved a few extra missions with Zimos and Kinzie.
Steelport also feels a hell of a lot smaller, customisation of clothes has been knocked down by over 60%, weapon choices are bland (wheres my sledgehammer? I wanna be Bob the Builder when he finds something he can't fix).
It kinda sucks how you already start at the top of the world, get a small kick to the nuts but you stand up and shoot the dude in the head and go back to the top before you even need an ice pack. Basically, what I'm saying is starting off with practically an army already loses the feel of struggle and conquest and you could roll in with helicopters at the blink on an eye.
Life is and will be hard on you. Stand proud to the challenges and you will thank yourself one day.
My path in life is not yet known. For now, I wander off the path and explore