What me and shadow did.
Instead of listing individual abiliities. We listed types of Buffs. Where in this case, a Buff can be one, or more, acutual Buff entity files.
Using this I was able to desing insanly advanced Abilities. I could (if I wanted to) even make abilities with very basic disision making.
Scrounge around this site-
http://wraithmodproduction.enjin.com/
for various ideas.
I also made soem diagrams for various types of abilities, and put the pictures on my Photobucket account. If you can understand then, I'm sure they'd be usefull.
http://s299.photobucket.com/home/EvilTesla-RG
In short, don't document EVERY SINGLE TYPE of buff and ability. Document CATAGORIES. General versions of similar types of buffs. And keep on specific example around for an example.
Better yet, IF You do this. DO it on the Modding wiki. It is weak on ability making.