Just a few more:
8. Middle-click to open apps without hiding circle dock, so you can open several apps at the same time easily (seconded ak_'s request)
9. Assigned icon spaces for applicable clicks, like some icons are very small or thin, so it's not easy to click on them (
EXAMPLE)
10. Per ring customisation, like 2nd ring has max 10 icons, 1st ring has max 6 icons, sort of thing
11. Have an option to open Dock Folders in a new ring (say, Ring 2) outside the default ring (called, say, Ring 1), rather than in it's own new ring replacing the default ring, but different folders you click in Ring 1 will change Ring 2 rather than opening a Ring 3 and 4 or whatever, but opening a Dock Folder in Ring 2 will open Ring 3, etc. (hope it makes sense)
12. Option to disable Dock Memory, ie, after you open Dock Folder called, say, Games, then click Pacman, it'll close, but next time you open the Circle Dock, it'll stay in the Games Dock Folder
13. Per icon background, can choose an image file for this, like each icon can have a black circle around it or a glass tray sort of thing (like
THIS), but unlike objectdock, can have both regular circle background and icon background
Just want to stress that I'm not trying to push for these, nor give you (VideoInPicture) a hard time, just want to suggest/give as many as much as possible to unlock the full potential of a great app.