Yep, there's many considerations including the overall towing capacity, GVM (gross vehicle mass) and the GCM (gross combined mass - vehicle and trailer) and other things like the ball weight as you say - it can get complicated for the unititiated. My truck has a GVM upgrade so I have additional load capacity so I'm all good there currently, and the trucks I'm looking at have even more so the only problem...car salespeople! Lol.