You're not the guinea pig here really. Chrysler did exactly this same thing back when the 4/5 speed 5-45RFE transmission was introduced (WJ). They looked for obvious failure (metal in the pan, etc), which meant a full replacement of the transmission and torque converter as a unit. Any other failure was considered to be an electrical (solenoid or sensor) or valve body issue, and those were simply replaced as a package. Not a huge big deal, and actually fairly non-invasive from a relative perspective.
Sure...you have the right to be upset. Within reason. New truck? No...that's overboard...and you WILL get Chrysler to shut down on you if you start making unreasonable demands like that at this point. Chrysler's (and other manufacturers) warranty does not give you a replacement vehicle as an option simply due to a failure. It says they will fix the issue and repair the vehicle. Your state's Lemon laws do not offer you a new truck for a singular failure either.
I feel for you...but just take a deep breath, relax, be REASONABLE and allow Chrysler and the dealership a chance to fix the issue.