From my experience a 4x4 half ton is good for about a 5000# dry weight or 7000# gross weight TT. That is about a 25 to 28 foot TT. Even that may be heavy depending on the TT model.
Much more than that and you will run out of cargo capacity.
Since cargo capacity is vehicle dependent, you will need to read the information on on the door jamb sticker to determine your payload limit. I also suggest at least 300 hp.
The folk who knowingly tow heavy, either tow very little or are willing to accept the wear and tear.
Good luck