If you look at the front suspension, you have only so many inches of up and down travel. The torsion bars set where in that range of travel your front suspension sits. Cranking the bars to lower the front end moves things closer to the upper bump stop. This means hitting a small bump will cause the suspension to bottom out, causing the rough ride. One cheap thing to try is trim back the upper bump stop to get a little extra up travel.

For the rear, you have a number of options:

For coil springs:
Coil Spring spacers or new, longer coil springs would give some added lift. Or some folks even add air bags inside the rear coils for adjustable lift.

For leaf springs:
Add-a-leaf spring, either purchased or junkyard spring pack would help give the rear slift block is another option, between the axle and spring. A longer spring shackle can also give some rear lift.