This is a rather impressive story that diverges from canon slightly before the first season with Lelouch being discovered by Clovis and returned to Britannia.
The writing is intelligent, most all of the characters are handled well, and the OC's manage to be deep without grabbing the spotlight (and the author is really cranking out the chapters despite this).
Your Mileage May Vary on a few points however, such as Lelouch's overall lighter attitude (the author's self-stated firm belief is that "Geass twists Lelouch" into what he was through the series) and the story's pace may be a bit slow for some.
http://www.fanfiction.net/s/6175861/1/Dauntless
((Side note if this is the place for it, but I'm curious how plausible the Zimmermans' "Unification Theory" is since I have been told by someone that in all likelyhood, the loss of foreign lands to conquer would result in Britannia restructuring itself into a police state, rather than go through the process of reducing its arms and altering its economy for the influx of now ex-soldiers as well as the expectency to pay the Numbers fairly))