I personally don't think the forum is big enough YET... to add a load of sub forums.... I think the Diary sub forum is a brill idea, and maybe TS 100%, but anymore than that I think the main forum could become really quiet...which IME deters new people from getting stuck in, because they think it's not worth it.
I'm on the fence about 100%, I don't mind reading about food at all, but know some people struggle with it, so if the demand is there, surely it's a good idea.