I don't know much about the criteria for fukoshidoin or shidoin....my teacher is a fukoshidoin and sandan in the USAF-ER. And he is awesome.
I wanted to respond to the goal-to-teach topic, though. I didn't start out doing Aikido with the goal to teach someday...like Rachel said, it was the furthest from my mind. Then I was just happy to put my foot in the right place. (I'm still happy when I do that right, LOL)
But now, 15 whole months (ha) into Aikido, I do want to teach one day and I do hope to open a dojo. Obviously I have a long way to go, but I'm pretty excited to have that goal in mind! I am not a firecracker, I'm a slow-burning candle. I don't have a talent for this, it takes me a long time to learn everything, but I'm determined that I will "get there" someday. I train between 5 and 7 times a week....as many times as I can, really. I'll be testing for 4th kyu soon....so I figure I might be experienced enough to open a dojo in say, 15 years or so, LOL!
But I don't see anything wrong with looking to the future....I'm just excited to share this art!
Now.....if I could just get over the panic I feel when I'm paired with a newbie! <grin>