The workspace pager can take up quite a lot of space if the screen configuration is very wide. (Or, in a vertical panel, if the screen configuration is very tall.) Turning on "show only current screen" can mitigate this somewhat, but not if you have one of those suuuper wide monitors. When "show window outlines" is off, the buttons in the pager just have to be click targets, so there's no reason for them to take up any more space than necessary for that purpose. In particular, there's no reason for them to be desktop-shaped. I think the most minimal tweak would be: - make the desktop buttons square whenever "show window outlines" is off. - make "show only current screen" unavailable/greyed out when "show window outlines" is off.
This makes sense. I have the same frustration when using a laptop, connected to two ultrawide monitors. The workspace pager takes up a lot of space, needlessly. This means there's less space for things like apps in the text-and-icons taskbar, and other widgets.