Before things get too out of hand, my suggestion is this and only this:
A hotkey that toggles the entire panel to show skills used, as shown in
Reply #2.
So, NOT individual skills, NOT showing both used/remaining simultaneously, and NOT a clickable button on the panel for toggling the view; these are things that have come up in the conversation, but I'm not necessarily in support of any of these ideas.
Regarding these; as Proxima said, showing both figures is confusing, would clutter up the panel, and there isn't enough space to do it anyway. Toggling individual skills, whilst useful, is not entirely necessary so I'm probably 50/50 on that one (namida appears to have ruled it out at this point anyway).
Having a clickable button, meanwhile, might simply be a case of expanding the panel to have an extra slot; I've created
this topic to consolidate this idea into something inclusive of current features.
Again, though, the primary idea as shown
here (and the one namida appears to have agreed upon) is the only one I'm promoting in this topic.