Spaces indicator (virtual desktop indicator)

I think it could be useful if the invisible Spaces (virtual desktops) were somehow permanently visible in the menu bar. This way, without doing a three-finger-swipe-up, one can see how many spaces are in use.
Maybe this indicator could consist of just small rounded rectangles, like small screens, each representing a space, with a number for each space. Or one rectangle, holding the total number of spaces.
Moving the mouse pointer over the rectangles could give an overview of all spaces. It could be clickable...