If you don't install Riverview, you'll be missing a lot of content. Plus, I really think it's a great world to play. My forum post shouldn't have RV crossed out. Only the way you combine the worlds and content in your game might change. Originally, I didn't know that the file sizes had to stay under that magic 204,800 kb mark. So I had to adjust which worlds I installed together in the same .ebc file. Sometimes just the order you install them in will make a difference and you'll go over that magic number for file size. When that happens, you have delete that .ebc file and reinstall that content in a different way, order, or combination.
So, yes, install Riverview!