Your 1/2 tone really limits you to lighter TT. And I doubt there is a best. We downsized from a 35 ft Fiver to a 30ft Arctic Fox TT but it weighs over 10,000 pounds.
Four people in a 24 ft TT will get very crowded and it will be impossible to keep the place organized with that many people in it. We found our 35 ft fiver overstuffed with us and two older teen boys. Generally 30 ft and below will get you in most National Parks assuming you can get a reservation. There are some exceptions.
Arctic Fox 25Y Travel Trailer
2018 RAM 2500 6.7L 4WD shortbed
Straightline dual cam hitch
400W Solar with Victron controller
Superbumper