I've followed a tut to make procedural rocks in Max. A much better way of doing things than by hand though I'm sure there are occasions where hand modelling might be more flexible. I hit the max vertices count in Outerra- which is 65K. So anything more complex would have to be modelled in two parts. Not really worth doing for a rock. The rock starts to look really nice around 300k polys but you have to be careful with the subdivision in Max as you can get locked out of the file because Max can't load it again. @1200K polys. https://drive.google.com/#folders/0BzHv3ffqAOUJaEoxSmNyNGlQcmc
In Outerra <65Khttps://drive.google.com/#folders/0BzHv3ffqAOUJaEoxSmNyNGlQcmc
This went through Mudbox where the seamless texture was painted on as a stencil. Mudbox seems a lot easier to use than ZBrush- much clearer interface though I still prefer ZBrush I think. The white lines on the rock were supposed to be highlights on convex ridges but I overdid them a bit.
I think it would be really useful to learn some more image manipulation for normal map creation. That way you could superimpose small bumps on larger bumps, rather than just all small bumps. I used a blur on the texture with some contrast to get the larger scale bumps, then added the higher detail to it. Prob a bit too rough though. Maybe get it smoother and then add some specularity for smooth surface. No spec on this. I think a bit of graffiti "Sauron woz ere" in red paint lol