It would be convenient to be able to define (either declaratively in XML or programmatically) custom virtual keyboards (codepoints + font-name) that could be popped up from the context-menu on any text field.
The string of characters produced on the virtual keyboard should be inserted into the associated text field at the .selectionBeginIndex location, or replace any selected text, if applicable.
Adobe could also supply predefined keyboards, but the important thing is that the programmer have the ability to define custom layouts and choose which codepoints the virtual keyboard contains, and that it be launchablefrom a custom contextmenuitem or that it be very simple and easy to tell Adobe which layout should be launched shoulda default contextmenuitem be dedicated to this purpose.
Slick if it could support programmer-controlled transparency, so what lies beneath it could be revealed if the programmer desired.
User-controlled transparency (with a slider) would also be a nice feature, though the programmer should be able to hide/show the slider widget.