Q: Can I have different upload rates for multiple cameras?

Answer: This is only possible if you have different computers hosting the different cameras. In other words, for all the cameras attached to one computer, they all must have the same upload rate. If you have many cameras, it is generally a good idea to split them up across different computers so as to reduce the load on a single system and avoid a single-point-of-failure. Hence, your system availability is increased.