Re: gpu usage
Usage reporting was at some point on their list of stuff that they might or might not want to implement, at some point in the future. In other words, they know it's missing but it is looooow on their priority list.
Maybe nouveau will offer something like that. But when you're interested in GPU usage, you are probably running stuff (CUDA et al) that needs the binary driver.
For the moment, another piece of usage info could come from the power levels.