Though from what I have seen in the Wild Swan publications, on at least one occasion each, a 56xxx 0-6-2T and a 43xxx 2-6-0 traversed the Coleford Branch, albeit on a trials run - Dean Goods 0-6-0 locomotibves were also based at Lydney, so with the plethora of Panniers, Class 14 'Teddy Bears' and other smaller locomotives, there is still a little variety to be had. Small layout with a 'mining' lineage can be most interesting...for example
Not quite the 'Forest of Dean' (though possibly quite the opposite in topography) but interesting nonetheless!