Recently moved to a Monk. Found the rave reviews to be right on the money and am loving this board. The speed, grip, tracking, carving, chop absorption all awesome. The only thing I wanted more of was pop.
So, with a little mod, I found it. Now you too can have the "hooligan" for most conditions and more of a freestyle pop board with the flick of a screwdriver.
Moving the fin in from the tip of the board a little stiffens up the end section just behind the thicker part of the board. I prefer a less tall fin for better switching/sliding and the 45mm Underground fins I use here probably have the same surface area as the Shinns as they are less tall but have a longer base.
Underground fins and their screws fit perfectly so all you have to do is drill one new hole per fin. It's a little tricky getting perfect centers and you must make a jig and make sure the jig fits the fins first or you will end up with either badly aligned fins or worse, useless holes in your board. Of course there's no reason you can't just use the Shinn fins.
So anyway. Now I have two boards in one. Standard mode: all the stuff you love about a Monk. And freestyle mode for more pop. In more pop mode you do lose a tad chop absorption but it's minimal and given the fins are further forward some carving surefootedness. But not that much.
Since you are only drilling through the end thin section and not through any wood core or anything I doubt there is any issue with new drill holes there. The new hole looks exactly the same inside as the existing holes i.e. the existing holes do not appear cored with any material inside or anything.
Anyone interested, post here and I'll tell you how I went about it.