Hi Blakey, I am no expert with FM8 but I make maps like what your describing with the zoom into region to show more detail. Personally I have gone for the realistic satellite type of map because when you zoom in you are still looking at something realistic wheras when zooming onto a mountain icon eventually you are into black and white lines of the mountain side which is not much use. So I think your plan is a good one.
Where to get textures ? Well we have the resources topic in the forum which lists many places but I would suggest CGTextures which is a free signup.
The "some professional" is Mike Schley who posts here. In fact he has a new map post here from a day or so ago so check out his work. I love Mikes work but I think is does not lend itself to the type of map that is easy to navigate by zoom.
In terms of automation I don't know. I doubt it but have a chat with Mark Oliva who seems to know FM8 very well.