That was really beautiful reply, i completely appreciate the effort.
How ever, as they said the key is the 0 squad, what ever they showed in early anime/manga about it being an actual key, is not really true considering that the zero squad them selves said that they were the key
My claim becomes more stronger that he actually did the sacrifices
Yes, they said that their bones are key, but they didn't contradict that actually key don't exist.
I predict that in the Soul Society is much more souls than in the Human world. Some souls are more than 2000 years old and there is no human even nearly that old, i would also say that some deaths in SS are numerous that in HW (since there are much more souls) since Soul is reborn in HW as Human and there is much more Souls all of them can't be reborned in HW, so thay go to Soul King and he dispose with them, thats why he have enough souls to gave RG member key and thats why he don't need to sacrifice
living souls (also down i will explain second possibility).
I would also say that he maybe have even power to create souls. Consider that Quincy destroy souls and that there were already 100.000 destroyed souls for key and there is needed a thousand of hollows for just one Gillian to be created, and there are many of them, so by real life logic population should drop instead of goind up.
Why would they meet the king?
Well, why not? Many people would like to meet god. Maybe someone in past tried to topple King, just like Aizen did.
the only way to go to the palace is using the cannon
If you remember how ichigo was transporting from one island to another by them using their power when they hit that mark on ground where it sends ichigo flying
We still don't know this. I'm pretty sure that there are other ways to go to Royal realm, otherwise, Aizen wouldn't reach Royal Realm, since Kukaku wouldn't allow him to do so.
there is no actual key to meet the king, it's the 0 squad that can make you meet the king or not by using their power
which means that to create those 0 squad you must scarifies 100k souls for each
By Yamamoto place where key is hidden is only known for CC of Gotei what's purpose od hiding the location of key if key is RG members.
Soul King don't create RG members with key, he grant them key (all RG members are shinigamis and were part of Gotei in past) Aizen is the one who wanted to crete key in other word he wanted to create life.
That's why i think that Juha itself could be that created key with 100.000 souls in past - when you use that method with 100.000 souls you got key but in the form of living human.
If soul king had such a power to offer like 500k+ spiritual power
he would have also killed all the holl
why would Aizen go there and kill him?
you know Aizen wont go on a suicide mission
1. Well i already explained his offering of souls
(+ Aizen would sacrafice 100.000 souls in order to create life, Soul King don't create new life, he just grant power, since i believe that he is humanoid Hyogaku i think that it is possibly for him to do so, like incomplete version of Hyogaku gave power to Inoue and Chad - this is second possibility).
2. Aizen could underestimate King, he little underestimate Ichigo in their fight in KT, also we don't know how far Aizen transformation in Hyogaku can go on, maybe at one point he would surpass even the king.
they came to soul society 2 times
one time was at the big ward before 1000 years, and now the other time
I don't remember that there was stated that they came 2 times down.