Procedral terrains are best for close up of rocks and dirt, but if you have veg covering it all up then just use standard there too. Otherwise you are just wasting resources. If you are animating it I would not use 4000 x 4000 yikes! My mac pro would not only be on its knees but gasping halfway to China!

A tip: to get really nice detail for your close up procedural terrain, go into the Terrain Editor, under the Proc. tab right click on the ball and choose Edit Function, then click on the simple fractal box and under the Simple Fractal drop down box on the left, choose Terrain Fractal, then with the slider below play around  with the Metascale, Largest feature and Gain to get some patterns on the ball. You can get some killer details with this. Good luck!