Currently, the way the [Spacebar] shortcut works doesn't really offer an effective tool.

It appears, that currently, it simply Selects/Deselects the last Studio Tool UI Element you clicked on. This can especially be seen if you click any item in the Top-Left Toolbar (if that was the last item selected at the top of the screen), or the Top-Right ViewBar (if that was the last item selected at the top of the screen) and repeatedly press the [Spacebar] again.

Where I have been really consistently missing the [Spacebar] shortcut however, has been a as a reliable shortcut to Start/Stop playback on the Timeline.

Therefore, I would propose that unless there are considerations I'm missing, that we completely kill off the current implementation of the [Spacebar], and instead reserve it for Starting/Stopping Animation playback. (with the exception of course that if a Field is active, it will create a space).