your right there is no way the show can just end here. Zuko has to find his mother, Angg has to discover that there are still Airbenders ouit there somewhere, And somehow someway Katara and Zuko have got to get together. The show ends in a way it souldnt with little questions answered and a whole list of thing that the avatar still has to do after it. The fourth season shou8ld be calle air and it sould be about the return of the air nomads, perfect right!