Would it be possible to ensure that all widgets have the same padding? Right now, the biggest aesthetic is the visual inconsistency of the padding. Some applets (like the mini Pager) fill the panel vertically or horizontally. Others, like global menu and icons have visible padding. So in practice you get applets of different sizes. Is there a way to force those applets that try to draw themselves without any padding to be smaller? Ideally, all items in the panel should line up and be the same size and have the same visible padding.
This is not possible because it breaks the plasma design decisions, The pop-ups would look out of place in that case
To add here... Except the padding issue that is totally up to Plasma to solve, adding any plasma widget in a plasma panel you will get the same results, currently all applets/tasks are perfectly aligned vertically or horizontally depending the dock edge