I came across this idea proposed on the Chinese forum about a suggested ending, which sounds interesting.
The basic structure is:
Inoda dies in the real world but his spirit/soul/brain data is uploaded to FOG. Asuna returns to her normal life with Kirito in real life but continues to have sex with Inoda in FOG behind Kirito's back.
It's interesting, because this basic structure can be expanded to many different directions. For example:
Route 1:
Inoda is revenged to die so Kirito is relieved. He believes he doesn't have to worry about Inoda anymore but Inoda still exists in FOG. Asuna continues to cheat and Kirito doesn't know about it.
Route 2:
Inoda sacrifies himself (not necessarily in a personally willing way) and dies. Kirito helps Inoda to upload his data on FOG so Inoda can still live in the game world. Kirito completely trusts Inoda due to his sacrifice, but he doesn't know that Inoda and Asuna are cheating in FOG.
Or Kirito allows Asuna to have sex with Inoda in game because (1) Kirito turns into a cuck and enjoys it, (2) Kirito feels guilty for Inoda's sacrifice, (3) Kirito thinks that it's just game so Asuna's cheating in FOG doesn't really matter, or (4) Kirito also cheats with Sugu, Sinon, and Alice.
An ending like this can create a lot of twists (which Fujino seems to like) and may satisfy both sides:
Some people want to see Inoda suffer, so now he dies;
Some people wait for a completely corrupted ending, so now Asuna continues to fall in FOG.
After all, this game is about SAO, or a virtual game world. With Inoda continuing to live in FOG, now this game gets back to its original context.
It may also raise a philosophical question: If there is a virtual world so real, is virtual cheating still cheating? Or is it just fantasy like an erotic dream?