well, in lue of Thran Lens, I think that this is costed fine w/o having an upkeep cost.
My point with Thran Lens was that I think it should be an artifact. Red probably benefits the most from this kind of effect, but there is nothing in the color pie which lets me think red is supposed to have it. It fits as an artifact much better (see, again, the Lens), and red can still use it.
It may even pass as affecting both permanents and spells as well as cantripping at only

, as it's a pretty narrowly useful effect. Dunno, though.