If you happen to be open to more revisions of your design decisions, I would respectfully ask that you reconsider your epic bonuses.
The 5E monster model has several deficiences, but that even epic monsters can be hit at least-semiregularly by a high-level fighter with a semihumble +1 weapon is not one of them. I can certainly sympathize with the desire to make something like a Demon Lord need a "more magical" weapon, but your requirements are out of scope for 5th Edition. If Magic Weapon cast at 6th level (producing a +3 weapon) isn't enough, the game can't handle your stats. One possible idea would be to require a combination that is unusual to the point of being rare, but still possible to achieve with the rules of the PHB. For instance, requirements such as "a +2 radiant weapon" that can be achieved by, for instance, a 5th level Magic Weapon combined with Divine Favor. (Or any other number of combinations that are possible within RAW).
I find that while I am attracted to your versions much more than the official ones, the main reason is that you have (quite brilliantly I might add) handed out the necessary abilities epic monsters should and must have. Area attacks. Mobility options. Battlefield control spells.
But all the rules-overhead of requiring especially magic weapons, sky-high AC and other bonuses, is not needed and in fact makes it mandatory to play the game in a decidedly 3E/d20 way. For my purposes those rules are an obstacle, a throw-back to an earlier era, a legacy way of thinking. Not that this is bad.... it's just not as
directly useful as it could have been
Especially since just making sure the monster has sufficient hit points (very roughly: double that of the official monsters) is all you need in that department. I know I have asked for this before, but now I do it with actual play experience: I don't want to switch paradigms when I reach the top levels, and suddenly hand out significantly more significantly more powerful items.
I know you have said you prefer the gods to be essentially untouchable, and I can't argue with that. But what I can say is: it's a shame your statblocks become mere curiosities. Battling gods and demon lords is part of D&D, and your statblocks are simply unattainable by heroes brought up to high level by official modules.
If I can instead offer a suggestion where your experience really is needed, there is one rules area that really needs some development: legendary saves. I would much prefer that my monsters doesn't "cheat", but instead aren't taken down by a single failed save. Somehow.
In the hopes you interpret my efforts in writing this as support and encouragement,
Zapp