We need to develop an orbiter for each of those planets, at Uranus, the five major moons are very different. They have unique geological history, so we need to understand how they were formed or captured. Uranus has a rotational pole that is tipped on its side more than the Earth, so we need an understanding of why that happened. At Neptune, there are a great amount of features in atmosphere similar to Jupiter and Saturn. And Neptune's moon Triton is of interest because of the methane geysers on it.