Which shocks for mostly work truck.

I'm pretty sure the shocks on my 08 prerunner are well on their way out. A while back I started noticing it doesn't much like curves anymore, tires are wearing unevenly despite clean alignment check, and it dives a lot when braking. I went to some discount shock website and filled in all my info and it gave me dozens of options ranging from 10 bucks a piece up to about 300, so I'm a bit lost.

Truck is mostly used for work (residential construction, lots of lumber hauling) so I was trying to figure out if I should use this opportunity to switch to something more up to the task. I'm assuming stiffer shocks would make it happier about some of the heavier tasks (and possibly make shocks last through more of such work?) However, my brother had a dodge 2500 which was much more up the task, much stiffer shocks, and my recollection is that driving it empty was a bit like skipping a rock on a pond. Every little bump on the highway sends the back end bouncing all over the place and the ride is just miserable if you've got less than a few hundred pounds in it.

Are my assumptions about stiffer shocks correct? Is there a good compromise between ride quality and ability to handle heavy hauling? I made no modifications but previous owner seems to have put some kind of lift on it, looks like ~1 1/2 -2 inch blocks. I'd say 150 each is around my upper limit for price. Any suggestions or info would be appreciated. And my apologies if there is another thread I should just go read, if so i missed it.