
Really, can't think of anything more ... unless you come up with something nice!
Guess all that remains as of now (since the creation of a selection before invoking the plugin is not possible as of now) is:
1) to include an icon that can be displayed in the plugin bar
2) to clean up unnecessary code if any to bring down the plugin size.
talking of which, maybe the "Fonts" button need not popup another window, but just put those sub buttons like Bold, Italic, Underline, Stikeout, Font, Size & Font Colour in a line just above the edit box. The sample preview would not be required as the actual text can be previewed in the edit box as is now.
Cheers!