The harmonies are not useless by any means, but they are somewhat fake sounding. With a bit of subtle application, there is hope. I usually run the diatonic with a mix setting of around 20-25 for a harmony part, and usually only use pitch a. I just set up different presets for different keys and scales and generally use a third down. I agree with the earlier post that it sounds more convincing if the harmony is the lower pitch.
