Not at all, barge away! ^-^ It's an open debate! :)

I assume she gave it to Mao because she decided he was the person who would fulfill her design; when it became apparent that for whatever reason he wasn't going to do that, she dropped him like a stone.

It's possible she might have given the Geass to lelouch at that young age, like she did to Mao, but then she fell into the hands of Brittania?

Yes, Lelouch should be fine as long as he's useful. Useful. That's the key.