Nice update. And I have a suggestion to maximize the spaces of the top, bottom, and side panels.
In Portrait mode, there is a smaller space for customization on the top panel while on the Landscape Mode there is a larger space. As per current features, same panel configuration appears in either portrait or landscape.
You have 10 panels to add to but the ideal maximum number of functions on top panel is 4 and any excess will be located in the side panel. Set-up: 4 Top function panels and 6 Side function panels which is still okay in portrait mode. But when you're on landscape mode, the top panel is spread-out to 4 functions while the side panel is squeeze-in the side pane; to 6 functions.
ADHOC REQUEST: Make the bottom panel be allowed for customization also. For example, I'm using hardware butoons for the zoom-in and out which makes the same function in bottom panel redundant and consumes larger space than other bottom panel functions. So, instead of the excess functions on the top panel be transferred to side panel, use bottom panel first, then side panel.
That's all. :)