[Mild spoilers for Legend of Korra]
THAT'S IT! EVERYBODY DIES!
Apparently, Bumi is not the norm.
In regards to age, that is. I think we all knew that Bumi wasn't the norm in terms of just about everything already, though.
It'd have been interesting to see some of the original characters outside of flashbacks, but it's probably for the best that we're getting this spoiler so early on. I'd hate to have expected them to show up and then have it not happen. Looks like your wish is probably not going to be granted, though, Mr. Flask. I'd still be shocked if we don't get at *least* one flashback to the original cast.