Nice set-up and even better for you that you got it as a package.
Does the handling have anything to do with the braking? You have a lot of weight compared to what you have had in the past. One thing that I have found with my set-up is that the braking is a lot slower than with my other vehicles and it takes a lot of getting use to each time I get in it.
As for the height and weight of the camper the truck should be able to handle it fine, maybe a little soft depending on the shocks and the springs, but this can be easily fixed. It will sure be different driving for you than the truck with just the cap.
Enjoy your set-up!
