Great! I'm glad to hear you sticking to your vision. What you are describing makes sense, especially with the oscillation of difficulty and power. I'll stick with it to continue to feel it out.
Just some more brainstorming: to help curb the initial "wall" feeling the introduction to this section has, make it so the Realm of War have some very clear bonuses (global or for R1) that this section introduces. Maybe prestige/sacrifices in future realms have small bonuses to previous realms, something like that. I imagine this "Quest" mechanic I have yet to see could have some impact like that, but because I don't see it right away, I'm more left with this feeling of having to climb a separate mountain than the one I've already been climbing. --and then I feel the exhaustion "groan" instead of excitement as a player.
Maybe a better way to put it is I was expecting a power spike for the Realm of War and not uncovering another difficulty layer. Its possible my own personal bias led to that expectation and subsequent frustration. Its just that uncovering a "Realm of War" sounded so cool, ya know? And it takes some work to unlock it as well. But when I did unlock it, it felt more like I opened a piece of coal for Christmas. Do with that what you will.
A quick note: of the effects you list as the RoW's positive "Bonuses", Sacrificing Batch + Cap are actually negatives as sacrificing in this realm is just plainly more expensive.
Anyways, again, great game. I'm definitely rooting for ya and how you refine your craft!