Well, the reason some air intake kits don't include as many parts as others, is that they don't need them, as they reuse existing parts.
Other kits have more parts because they fit differently enough to warrant them for a better fit.
The only thing cat-back really means is that the system does not start at the manifold, but at some point after the converters. In the case of the Ford F-250, that means the first clamp joint available is that behind the forward resonator. Evereything between the converters and the end of that resonator is welded from the factory for ease of assembly. None of this is a plot or conspiracy to foil anybody. In the case of air intakes, find the one you like, buy it, install it with any parts included PLUS any original parts needed, and you will be happy. You will still get EVERYTHING required to complete the job. Some just use more original parts than others. It's a matter of how each kit is designed.
In the case of exhaust systems, what is available are ALL better than the factory setup, but none are perfect because a certain amount of assembly ease must be figured in, and that would be a lot tougher if they had to make a kit that bolts to the rear of the converters instead of in back of the first resonator. To get that last degree of improvement, one must do a bit of "rolling one's own" at the local muffler shop, any of which can easily do what I described in my previous post.
So take it a little easier, do your homework on finding the right parts(read the WHOLE catalog) and try not to be so obsessive, since you DO know how you are. Best of luck in your future endeavors!