At least one needs to be familiar with near gross, near rear CG operations.
Despite being fully prepared for it, I can still remember the first time I flew a Skyhawk with 4 people. A completely different airplane even within limits.
One good thing with my old 180hp Maule - 4 people and full fuel wasn't really an issue. Off load 10 gallons and you could even carry a decent amount of baggage, more if you moved it forward. Bad news was it was slow no matter what. Trade-offs
Exactly, if you want to haul weight with low horsepower,mother trade off is speed. There is no free energy in airplanes.