Heck, why not go all out and add 5 more feats, while also slightly changing the name of the Tattoo ritual to Enchant Mystic Tattoo to encompass all of them?
Way of the Shimmering Moon [Mystic Style]
Prerequisites: Int 15
Benefit: Your unarmed attack counts as an orb. You may use the ritual Enchant Mystic Tattoo to apply any magical orb effect to this feat as if you were using Enchant Magic Item to create an implement.
Special: You may select one Mystic Style feat in the Heroic tier, and one in the Paragon tier. If you have more than one mystic style feat, you gain the benefits of only one at a time. You can change which feat you benefit from as a minor action.
Way of the Dancing Willow [Mystic Style]
Prerequisites: Int 15
Benefit: Your unarmed attack counts as a wand. You may use the ritual Enchant Mystic Tattoo to apply any magical wand effect to this feat as if you were using Enchant Magic Item to create an implement.
Special: You may select one Mystic Style feat in the Heroic tier, and one in the Paragon tier. If you have more than one mystic style feat, you gain the benefits of only one at a time. You can change which feat you benefit from as a minor action.
Way of the Eternal Tree [Mystic Style]
Prerequisites: Int 15
Benefit: Your unarmed attack counts as a staff. You may use the ritual Enchant Mystic Tattoo to apply any magical staff effect to this feat as if you were using Enchant Magic Item to create an implement.
Special: You may select one Mystic Style feat in the Heroic tier, and one in the Paragon tier. If you have more than one mystic style feat, you gain the benefits of only one at a time. You can change which feat you benefit from as a minor action.
Way of the Steadfast Column [Mystic Style]
Prerequisites: Cha or Con 15
Benefit: Your unarmed attack counts as a rod. You may use the ritual Enchant Mystic Tattoo to apply any magical rod effect to this feat as if you were using Enchant Magic Item to create an implement.
Special: You may select one Mystic Style feat in the Heroic tier, and one in the Paragon tier. If you have more than one mystic style feat, you gain the benefits of only one at a time. You can change which feat you benefit from as a minor action.
Way of the Eternal Soul [Mystic Style]
Prerequisites: Wis 15
Benefit: Your unarmed attack counts as a holy symbol. You may use the ritual Enchant Mystic Tattoo to apply any magical holy symbol effect to this feat as if you were using Enchant Magic Item to create an implement.
Special: You may select one Mystic Style feat in the Heroic tier, and one in the Paragon tier. If you have more than one mystic style feat, you gain the benefits of only one at a time. You can change which feat you benefit from as a minor action.