Screen Region Selector
I love Parsec Gaming. It has revived so many old and cool games for me which I can now play with my friends, but a lot of them feature a split screen mode, which is a little difficult on the viewer because the stream quality on slower connections can't really go over 720p without beginning to stutter and buffer, and at those kinds of resolutions, having your screen cut in half makes things difficult to see. I know the underlying problem will not be solved with this sort of feature, but it would still be nice if the client and/or host could select a screen region to let the client have a somewhat fullscreen view of their perspective, without sending over unnecessary data, such as their friend's perspective. That way more quality could be extracted out of the same internet connection, as on the host machine you would only be streaming a fraction of the screen, rather than its entirety.