The reason those waterfalls, or the ones that were popular a while back with other tileset conversions, or basically any waterfall in any tile ever, do look "ugly as sin" is because they have nothing to do with the perspective of the tileset they're in. JJ2 uses a much more complex graphic style than JJ1 and that lesson is not being learned in this one crucial field. Compare the water pools from Jungle and, in fact, Colonius - they're not flat and full-tile. In JJ1 they would be, but this isn't JJ1. I've used this example before, but here's what waterfalls (and heck, water in general) should look like in an isometric game like JJ2.