You will gain better alignment for sure (and better handling). Better flex would probably depend somewhat on dynamics, although the lower CG might help some as well.
Is your Ranger a Supercab? If not, you'll likely need to swap to 6" coils as well to get your camber to where it can be aligned (maybe run a small spacer with the 6" coils if you still have some leeway in your camber bushings).