I've decided to work this way:
I do sketching in photoshop and come to a 'rough' image of all 18x3 tokens based on craig's
then I'll rebuild all images in Illustrator to get a vector image.
This way you can scale it even to billboard size and it'll still be sharp.
I can also make sharper curves this way instead of drawing by pen or mouse.
it's also much easier to change the image like mentioned in the oars and so.
It will take a lot of more work, but I'm not in a hurry, nor is the project. I'm always goaling for the best results.
Here are some previews:
First I've traced the animals and placed them on the building I drew apart from them:



