I tested your app to be used as a taskbar. It works good with some limitations. What I did was to narrow the size of the launcher to its minimum width to the left of the screen then open a normal app as a large window. It fits. Then I can just use the launcher as a dock or task bar to switch from one app to the other.
The limitations are 1/that when you narrow the launcher to its minimum width, the Icons get spaced out and 2/by default the apps open in full screen rather than floating.
Therefore I suggest that you adapt your existing launcher to create a vertical dock that would fit just before a large window, and use mini icons that by default would open the apps in a large floating window.
Doing that would make your app unique. The taskbar app in android does that too but the fact that the bar is at the bottom limits the number of icons that can fit within it.
I’m not sure if I understand you well but why don’t you use the floating menu which is designed exactly for this?