The beauty of the banana split martini is that you can change up the ingredients just like you can with a real banana split. By going with a flavored vodka you can add your favorite "topping." Strawberry, pineapple, coconut, or even more chocolate or banana are all good options and there are many others that you can experiment with.
Then there is the choice of garnish. You can go low-key and stick with the customary banana slice, or a lone strawberry or pineapple slice, maybe adding a cherry. There are strawberry and chocolate syrups drizzled in the bottom of the glass, and the decadent chocolate dipped strawberry or banana. However you decide to dress up this drink is completely up to you.