Illustrator is really good for some specific things but not for map makers in particular. It's great to draw lines/sketches, drawing shapes/concepts, designing logos.
Everything looks clear and sharp in Illustrator. Because of that, illustrator is poor to handle textures, gradient and if you have a lot of small elements (if you draw every single trees for example).
Making maps is definitely not intuitive if you are used to raster programs like Gimp. The method is very different if you intend to get similar results.

Photoshop vs Gimp : I use Photoshop and barely used Gimp, so I can't tell which is best. They are different and there is some learning curve to figure but once things are settled, most people I've read agreed that Gimp is pretty decent.

Personally I stopped using PS long time ago, because I found better alternatives in terms of price. I tried a lot of software out there and every single one is doing its job well. All comes down to which one feels the most comfortable for you yo use.
What are you using Voolf?