The point is, that this Card should have the Mage and the Restoration Keyword, since it add to these cards the mage boni mentioned in the card's text and also this Card triggers the Restoration Keyword.
So in fact, it can add 10 to your lowest recource, 10 recources from the Card you have chosen, and the extra 8 recources for the Mage-Bonus. I don't think that this Card should not be a rare, since alchemy for example can trigger, well played, the restoration keyord twice, even if you need an extra round. Probably i have to add a drawback like "replace a random non-common with....".