Thank you, I think that should work well enough for me. There is still an issue if I want to push dusts between machines over the main bus (e.g. a producer of carbon dusts?), but I can just do the minimal size dust conversion at the ore processing output and oredict for those at the dust collection area.
Somewhat related question - do items in item pipes consume bandwidth even if they fail to be routed? Asking since if I want to have push-based item distribution I would have items sitting in item pipes and waiting for compatible inventories, which could use up some of the bandwidth.