The problem I have is that you can say all these things are "built," "beefy," and "heavy duty" but you're not giving us any numbers.
"Heavy duty" means a lot of things to a lot of people. Anything rated for more than "stock" is considered "heavy duty." Your "heavy duty" airbags may be rated for more than the stock airbags, but are they rated for the 4500-ish pounds of weight that will likely be on this truck's rear axle?
The terms "built" and "beefy" also suffer from the same problem. There's "built/beefy" as in more than stock, and "built/beefy" as in designed for the intended purpose. Those can be two different things.
I have no doubt that if you use the correct components, and do quality work, what you want to do will work marvelously.
You can build that truck out to tow however much you want it to tow. The onus is on you to do your homework to make sure the parts you choose are up to the task.