IMO the threads that are started for each topic are enough. it would be confusing for newbies, eg where they are supposed to post what topic and reply to where.
in this event you would still have people opening wrong threads under wrong forums etc. you would have the problem of duplicate thread topics been opened in different forums.
good point about areas been stale, may not have enough demand to keep sub forums running.
IMO i come here for stock talk, if i wanted to go to a software forum i would go to a software forum etc.
just my opinion.