i think it would be worth a try to put a quality spring pack in the rear only. you will spend a couple hundred tops and your ride will improve dramatically.
if i read your post correctly, you're running 2.5" add a leafs front and rear to fit your tires. add a leafs are super stiff. you have no real weight in the rear to even move the springs when you hit a bump. think of it like driving a 3/4 ton + pickup unloaded. they have stiff springs for carrying heavy loads. unloaded, the back of the truck will bounce and hop all over the place. with a load, the suspension actually works(the springs flatten/shocks dampen). hd trucks drive much better loaded.
at least up front, you have the weight of the engine on the springs. the only compression/rebound you're getting in the back is through the tires.
it's worth a shot. that's one of the 1st suspension mods i did to my cj 12 years ago. i didn't have the $ for a lift kit but my 4" springs were so stiff, the slightest sidehill would feel like it was going to roll over. i left the stiff 4" springs up front and did a spring over with stock yj springs in the back. the change was incredible. the spring over isn't an option for you because it will be too tall in the back but you can get the same result with softer springs.
another(even cheaper) option might be to take the aal out of your rear spring pack, add a 1" lift block, and get the rest of your lift by making longer shackles.
there are other options too but the bottom line is, you can get the back to work for next to nothing and your ride will improve dramatically even if you leave the front the way it is for now.
