That can work, Im not a big fan of blocks, but if kept to a minimal they aerent to bad. You might have a slight increase in axle wrap if the springs are soft enough in the first place. On my old truck I just made up some 7" shackels since I didnt have the coin for rear springs at the time. Gave me about 3" of lift and helps corrent the pinion angle a bit. Your front end is definately up there!
I was just curious about how high your body lift is. It might be of some benifit to remove it if you think the springs are too much lift.