I really like Ai and Yu. I find their names very fun to pronouce. I remember when I first saw Ai; I took quite a lot of interest in his design. CC have very unique color scheme; he seems to be consists of gray...but not entirely.
Boris always seems like the odd one out. I can never tell whether he is in extreme joy or in extreme PAIN
It seems a lot of recent deviations are drawn in oekaki. What oekaki do you use?