I liked the first world, but the second one suddenly got very frustrating. Not least because hit detection with the balls is very buggy: they often go through(grass, platform, box) tiles when falling; usually the ladder's top tile stops them, but sometimes it doesn't either. The level ending is also strange because in world 1, once all flowers bloom, the level ends; in world 2, most often it doesn't, and we have to wait a few seconds before Pete starts his victory dance. This seems to be connected to moving balls on the screen, but I am not 100% sure.
Finally, the countdown/scoring at the end of the levels is very slow; speeding it up would improve the experience for those playing on real hardware (Vice's warp mode helps a lot, but it shouldn't be needed).