One trick you can use for a heavy tongue weight trailer is to make a small "dolly" with a trailer hitch and a crossbar with tires on it, then bolt a trailer ball to that, so all the tongue weight is on the dolly, and not on your suspension. A buddy of mine used that set up to haul his fish house onto the ice when it was too thin for his truck, worked really well. It puts another pivot point in the tow line, so backing up is harder, but for straight pulls, it works very well.