What onionhead said about creaing is prolly the best way to go. another similar aproach would be using the sculpt geo tool to pinch the sharp edges if your mesh is dense enough
I think sculpting is no option. I dont know a "intelligent" decimation Programm with a change of the edge orientation. The hard edges will look like a sawtooth without retopology from hand. Computer generated decimation is in my opinion one of the most underdeveloped technologies.
I'm a max user and the patch grid technique is time consuming, it's actually much faster and easier to sculpt it in zbrush, 3DCoat or Mudbox. Max also has "Substance materials" (I think Maya does too?) which are preset materials with modifiable parameters one of them is "Desert Sand", this has various paramters that you…
Retopo is coming around, mudbox2014 has some great tools for this. You draw out some guides along important areas and it figures out the rest. 3DCoat is pretty good at retopo too, similar functionality. zBrush is probably the widest used but most under developed when it comes to retopo but decimation master does a great…