Ok recently after having my blazer for a little over a month i noticed how hard it rides over little bumps in the road, When passing the bumps about 25-30 mph the rear end hits hard and you can hear a clang-clank like a hard sound and the rear end hits roughly, I am looking to replace the leaf springs with they help soften the ride or would i have to get new shocks as well i plan on doing both but just the leafs for now here is the link for the leafs

And here is the shocks So with all of that will my ride overall be much more softer

 

I put new 4 leaf packs on mine recently (and coil over shocks at the same time) it stopped the rear rattle/clunking but if you go this route expect a stiffer ride (does not bother me its a truck after all not a Cadillac) I paid $200 for my new springs but they had a 2000 lb. load rating vs. the 1350 on the ones you linked, Overall i'd say I am very happy with the outcome.
One bit of advice though if you order those start liberally drenching your leaf spring bolts with pb blaster daily and start it now.

 

ok thanks