Samulus, the current plan is for three basic colours, a dark grey/black, a tan brown and a light brown. I might do some more if the three don't seem to give enough variation.
For cheap plastic figures, the detailig is pretty reasonable. There are exposed ribs and shoulders, and so a touch of bone coloured paint, looks good.
I am not going overboard with my zombie figures, as frankly, they tend to be on and off the table, and there are over a hundred to paint in total, so its fairly basic paint schemes.
My more speicalist zombies and bad guy evil things, will probably get more painting attention to detail, so as to make them stand out.
Right back to the painting table.