Thanks for the reply.
Well i´ll be adding lpg tank instead of the wheel reserve, since paying for gas is unreal here. So that will be some constant load. And i´ll make camper conversion that will be sitting in it most of the time.
I´d like to get the airbags, but from what i´ve seen they are 500 bucks and more. Which seems quite a lot when i won´t be carrying heavy loads and towing a lot. The leafs are in somewhat good shape. The rear is not sagging in comparison to front, but of course the torxions saged a bit too probably.
Overall i´m leaning foreward to the option of blocks between axle and suspension, because it won´t affect stiffnes but will add the height i want for the least money.
Thanks!