The best perofmrance for MSE walls comes from using the AASHTO specification. 100% passing 4 inches, less than 15% passing 75 microns, UC > 2 and PI < 6. In addition no shale, deleterious or organic materials. Chemical limits if you are using steel reinforcements. pH > 3 for all geosynthetics and < 9 for polyester reinforcements. A few other more minor points as well you can pick it up from the specificaiton.