It seems that GF is trying to find new smaller markets which the others do not go to and that is never a bad thing. These smaller markets probably cannot support an A320 and hence the smaller jets. The demand may me small but with none of the other airlines serving them means potentially high yield traffic. The question is how long this will last before the other airlines also come into those markets as well and then GF is back to the same old story.
Even some of GF's current markets are becoming weak and if they are to be saved from the axe have to be transferred to an Ejet.