This aura, as it stands, isn't good enough to train. Its requirement, Empowerment, is much better for generating pips.
Improving this spell enough to make it worth training shouldn't take more than a small tweak. My suggestion is to make it trigger on any spell with 6+ pips OR 1+ shadow pips. This would make the 5 pip + shadow pip Darkmoor spells trigger the aura, which they do not currently do.