NOOOoooo.
It sort of DEFEATS the ENTIRE purpose of Aang entering the Avatar State, it is supposed to be gloom and doom, not bright and happy.
Kimi wa ne tashika ni ano toki watashi no soba ni ita
Itsudatte itsudatte itsudatte
Sugu yoko de waratteita
Nakushitemo torimodosu kimi wo
I will never leave you