Sounds like a great idea.
Having said that, though, I'm not really a fan of the custom calendars, really. They create a higher barrier to entry for new players. Besides, I can never really keep them straight. "What years is it? 7 IY? How does that compare to this 3 AU date? Does that make it 3 years ago, or 4? If I know that it happened on July 6th, 2011, then was that before or after 3 OE?" God help us if you actually use 3 or 4 different schemes based on different landmark dates...