And that would make your submerged wizard into human artillery; 9 power, 10 control for offense, 6 power, 7 control for defense.
Also note that this is far from being as min-maxed as it gets. A really min-maxed character would have an Item of Power such as a wizard's staff or book of shadows or robes of the archmage that gave +3 refinement with +2 cost reduction so he would get even more magical power at 1 less cost.
I caution you on the tattoos. I'll tell you the same thing I told a buddy of mine who wanted tattoo focus items. Reread the dresden files and you may notice a few instances where Harry overloads his foci and they explode. Now imagine that instead of a wand, its your arm. You could do it, but it's a bad idea. Someone else mentioned the idea for refinement, and I think you could even do it as an enchanted item without it becoming a problem.
You want other incoginto foci, look around your area right this minute. Book, chair, shoes, beer mug, cooking supplies.
yaha! some one else who has a butterfly knife, with what would you enchant it?
To take a page from the TV show ( I know, I'm a heretic) drumstick for a wand a hockey stick for a staff. The drumstick is one of my favorite foci idea, imagine seeing a pair of drumsticks on some guy's backpack, would you ever think about it?
Nothing wrong with that. I have PCs and NPCs who use those.
And my campaign has an organization who actually make Hockey Sticks of Doom....for the right price.
that gives me a good idea for a wizard hockey player =)