You would be bastardizing the boat, for one thing, which will make it difficult to sell down the road. Secondly, you would compromise the righting moment of the boat, which is designed in factors between the center of buoyancy and the center of the combined effort of the sails and the center of gravity. Boats that are designed with shoal draft keels have heavier keels than deep keels, which go deeper (that is one reason why the price of an optional shoal keel on a new boat is an upcharge). I have sailed all over the bahamas in a boat with 6.5' draft and got around just fine. There might be some places you want to go where you have to wait for high tide, but they are fewer and far between. The Islander 36 is considered to be a pretty decent cruising vessel that sails very well and it has a good reputation. I wouldn't cut the keel off. Keep it original. You won't regret it.