We had options years ago and decided, and still do to this day, to stick with a truck and a travel trailer (opposed to 5er or MH). Why? Because of the separation value. We don't have to have a Toad, and we can park the camper and use the tow vehicle to run around.
There's pros and cons in every choice. This is our logic, your's can definitely be different, and that's perfectly OK. There are no rights or wrongs. All that matters is your decision fits your lifestyle and you are happy with it.
From all that I've gathered, read, studied, and learned about truck size and RV trailer ownership, this seems to be a near-miss rule:
F150 / 1500 vehicles OK to tow trailers (any kind) up to about 23 feet with no problem. (Gas)
F250 / 2500 vehicles OK to tow trailers (of any kind) from 23 feet to 31-32 feet with no problem. (Gas)
F350 / 3500 vehicles (single wheel) 31-36 foot trailers with no problem (Gas)
F350 / 3500 vehicles (dual wheel) pretty much anything (Diesel), Dual wheel best for longer, heavier Fifth Wheel trailers.
Diesel anything will tow the same trailer easier than it's sister gas model.
Generators? I don't know of any travel trailers that come with generators, but have bumped into a few owners that modified their campers to have one permanently installed (very creative ways actually). Most travel trailer owners will carry a portable generator for those that camp off the grid.
