Customize multi-stream video sizes and chat size

When streaming from multiple sources on a server, you either have to have all the videos the same size, or have only one stream focused where all the other streams are much to small. It would be nice to have the ability to customize the window size per stream so for example If I wanted to increase the size of a gameplay window over another, without making the other stream oppressively small, being able to just stretch the one video OR shrink the one I still want to see but not as focused. Also if you want to see a DM chat, it automatically takes up half the screen, should be allowed to shrink that if wanted :)