Then your shocks are whooped. The coil sprung trucks drive much nicer than the leafsprung ones. The 08 and 09 have essentially the same suspension. Do you have the plow-package springs in the front of yours maybe? There are different spring rates available from Ford depending on how the truck was spec'd. Either you have stiffer springs than your FIL's truck, or your shocks are no longer effective, and his are. If his rides well for you and yours doesn't, maybe try the shocks he has.
And yeah, 2 1000lb animals, half another one, and a boat with a camper trailer on the back would likely overload a 3/4 ton truck.
No need to start getting ignorant with people. I spend all day getting in and out of dozens of different superduties, I'm pretty familiar with how the different cab configurations and suspension types ride. The only one I've ever ridden in that would be considered "smooth" while empty was on a full Carli suspension set up, with tuned reservoir shocks and custom springs front and rear. They're heavy trucks. They ride as such.
Softer springs is not 'dumb' if you're not using the springs you have to their potential. You stated the truck doesn't haul and you don't want a stiffer ride... The only way to achieve that is to decrease your springrate. People add leafs to hold more weight, it's the same principle. If you never add enough weight for the springs that are in there, you have the option of removing some, or going to a thinner leaf.
Define "brutal ride". You can't drive a truck capable of carrying over a ton in the bed and expect it to ride like a car. Most vehicles on here are near or over Max GVW, that means they're adequately working the suspension. I don't think there are many on this site looking to figure out how to make their HD truck suspension ride softer.
I'll say it again; shocks only control the spring. The spring is what dictates how "soft" your suspension will be. Dampening stiffness is increased if you are running hard or fast, OEM shocks have adequate valving for lower speed use. So unless you find that you suddenly "have the time" for getting rebuildable shocks and spend some time getting them valved to what you are looking for, you're not going to find a suitable ride.
I always have a hard time with people driving a 1-ton truck complaining about ride quality while empty. That's not what they're designed for. It's like complaining that your family sedan squats in the rear when towing a trailer.