well many good forums i know of hv mostly 2 subforums for each forum
neways
its totally upto u guys
u guys are the owners, not me
but i just think that making sub forum for each phone company, for each console is really bothersome

and another thing,
u said that as the contributors will increase, they will start contributing
but do u think that they will care abt these rare topics???
i myself hv pretty good experience and trust me, users only care abt what they get and they will start contributing only the easy stuffs
plus, when they will see that even the staff members dont care abt those sections, why should they care???