The story so far

The Avatar series could potentially make 2 more shows after Legend of Korra with an earth nation avatar and a fire nation avatar and I for one would not protest.

Avatar could come full circle and do another show about the next Air Nomad Avatar (someone who was different from Aang) and even another one about the next Water Tribe Avatar and so on and so forth and I would not protest. 

Avatar could do another show about another Avatar centuries before ATLA or another avatar thousands of years after and go out of order and tell any story in any era they want and I would not protest.

waking up in 2020 be like. gotta check what catastrophes, riots and natural disasters i have missed during my 5h sleep