Roll20 has some pretty small storage capacities. 100mb free, and a 3-6gb storage for pro users is pretty small. I know firsthand that per-user storage can be pretty messy, leading to very small amounts. Other storage providers, such as Dropbox, One drive, Google drive, etc., give users lots of data. Setting pointers from local storage to offsite storage would be incredibly useful. Even if just for images and music.