This is a feature request: I think it would be useful to have several sets of highlighting keyword which are coloured in different faces. For example it would be useful to be able to color all org-mode keybindings in a different face than the normal edit commands, thus allowing even faster selection of the correct keybinding.
I haven't checked your source, but I would assume that implementing this feature is not too complex. Please let me know what you think of this feature.