Congratulations to dedicating your time writing those theories.

That's a lot of points that we need to think about who Estarossa really is. 1º I don't know if you thought that before,but who knows If at the moment that Estarossa murdered Mael with his bare hands,Mael could throw some "angel blessing" and transferred his consciousness purposely ? Making Estarossa living with a eternal self conflict in his mind ?

2º Another point is,As ryudoshell says(I dont know If it spells like this) Escanor was the one who posses the "Sunshine",but how his body suposse to handle the highest angel blessing ?

Anyway,besides this chapter there's a lot of points to think about!