I haven't looked in to take a look (at least not since the academy days,) but I thought the roles they use is Tasker and Taskee... and no indication that Dom/mes, Tops, or Sadists cannot accept tasks... nor that submissives, bottoms, or masochists cannot give them.

If you think you have some good ideas... offer them up as tasks.

I suspect, in some cases, subs (et.al.) might have some insights as to what kinds of tasks they crave.