Well, to obtain the level of detail I need for my models, I usually resort to sculpting a low-poly version of the model in Zbrush where I up the poly count to say 10 million polygons in total. I get the bump mapping and color textures from that, and also cavity textures which accentuate small cavities in the surface by adding shadows to them (something simmilar to an occlusion map rendered in a 3D package). If necessary I get the occlusion maps from the 3D package, in my case its XSI.
To mix all that up I need an image editor which can work with layers and composite them. I use Photoshop, but I hear Gimp can do pretty much the same thing, never tried it personally though. I also use Photoshop to add extra touches to my color texture, like replacing color coded areas with actual textures, cuting, pasting, erasing where needed and so on.
So I use three programs to get something like this:
I seriously doubt you can get that kind of look with a built-in image editor in Maya. I've been wrong before, of course. I thought Blender was crap until I saw what people can make with it. But as far as I know, the above combo is top-notch when you're going for detail+low poly modelling. And want to do it before you die of old age. 
