I am wanting to make my 2016 Heritage run at 100%. By no means am I a mechanic. My question is: would installing a fuel pack on my stock bike do anything? Other than waste $300.
Are you referring to a Fuelpack or the Fuelpack3? Either one will give you a little bit better engine/fuel management but the FP3 has a greater capability to change the parameters of the ECM.
If you want your air fuel ratio to be correct and your bike to run cooler, tune it regardless of modifications. I am heavily in the camp of tuning stock bikes...
FP3 is a worthwhile investment even for a stock bike. Runs noticeably cooler and crisper after tune. And you know that you probably won't leave it stock forever.