i dont think we'll see turboprops to ballina for some reason...it's a market that competes directly with jetstar, a market that is primarily a leisure market and focussed on lower-cost fares. business people choose to fly rex, so virgin will neither change to turboprops (unless it starts double-daily flights in the aim to compete with rex - a small market as it is given the recent change in schedule) as such, virgin also will not likely offer business class as a major feature on their ballina flights. the lack of frequent flights mean business people in the region are likely to go to the gold coast for flights (and i know of a few people from the region that will do just that, whether business people or otherwise).
now in terms of coffs harbour, these services are operated by e190 aircraft, which arent all installed with business class yet (note that hervey bay also doesnt have business class on sale - nor do albury, rockhampton or launceston out of sydney..). there is potential, given that the competition is qantaslink q400 aircraft, that props will start on the route (PLEASE bring back the early-morning service from sydney!!) this could be why business class isn't being sold. but then again, it's likely just because there's no business-class equipped aircraft operating on the route.