Yes I noticed it and that's great but it doesn't give you audio play/pause shortcut. It doesn't work on the expand arrow for example (that's an idea for Apple !).

I have to make compromises if I want the play/pause control then I'll loose the brightness or volume because the shortcuts are limited to 4 max even if the touch bar is mostly unused black space on the left most of the time.

If that's the case, you can just go into System Preferences and make the expanded view the default.

Yes but then you loose the app dynamic controls and the benefits of having a dynamic touch bar.

Weren't you just complaining that you'd rather not have the touch bar and would rather have the default keys? It sounds like you're looking for a scenario that's not possible. Either you have fully dynamic keys or you have the option to customize the entire row. I don't really see a way you could have both.

You can easily add the play/pause button into the touchbar in the keyboard preferences: http://i.imgur.com/WMizuQD.jpg