You're not reading what I've said so far. I'm saying if we go by the absolute high end interpretation then Mundus should be 7D or more. But if I was pushing this point I would be asking to have the Et Ada moved to
1-C, I'm not; I'm suggesting the et Ada be moved from
2-A to
High 2-A possibly higher, that Sithis be moved from
High 2-A to
low 1-C (possibly at least) and that Vivec either should lose his
2-A likely higher rating or have it changed to
unknown.
To be High 2-A the et Ada only have to be 5D. I've provided three, main, separate and distinct pieces of evidence to support this (that while somewhat vague tend to come from reliable sources), each alone is enough to make the Et Ada 5D at least. Let's take all my sources on their own for now with one additional I'd like to expand upon.
1) - There are multiple sources that mention the Daedra's hyperagonal morphology, I've explained how this word very likely refers to higher dimensional objects, due to how it's used in the context of the source and by linking the real life mathematical concepts it is based on, both of which I have either linked or inscribed above. Now let's ignore everything but this point. In this case let's just assume that Mundus has the typical
4D. For the daedra to be hyperagonal they would have to supersede the
4D of Mundus... making them 5D at least. So, accepting this one point is enough to justify the Et Ada up to High 2-A (since they should all scale to each other) and, since he (and his counterpart) supersedes them, Sithis to low 1-C. In this example, Mundus doesn't even need to be higher dimensional.
2) ― Time is said to have 2 dimensions on Mundus. Due to how the Elder Scrolls behave. I'm personally aware of 2 sources for this (there may be more). One comes from a servant of the Daedric prince of Knowledge and the other from the librarian for the mages guild in Skyrim; reputable sources that I have linked and written above, hopefully you read them. This would make Mundus 5D (since time and space dimensions are treated as the same here). This source isn't all that vague and multiple dimensions of time are pretty clearly described. Gywn seemed to agree that this point had some merit before I even added the 2nd source backing up the same point. Again, this alone should be enough to move the Et Ada to High 2-A; since they exist on higher planes and Aetherius is described as a place
beyond time and space by a description of an attack in Skyrim, basically what amounts to word of god. At the minimum, it should be beyond the typical 4D to classify as beyond time and space which is all that's needed for the high 2-A rating.
3) ― Finally, there is the mention of movements at strange angles, non-cardinel directions and how you must move "sideways" in place to enter adjacent realms or the parallel version of Nirn known as Lyg. Now these are the vaguest of the sources and I freely admit if this was the only argument I had I would have never suggested an upgrade. This is the source that if taken at its highest interpretation could make for a 7D or greater Mundus (if combined with the extra temporal dimension). But like I said I'm only arguing for High 2-A for most of the gods here.
4) ― Mundus has parallel versions (
Lyg being an alternate version of Tamriel) and branching parallel realities caused by dragon breaks (
http://elderscrolls.wikia.com/wiki/Dragon_Break). According to superstring theory (
https://phys.org/news/2014-12-universe-dimensions.html) this would make Mundus a 5D construct. Oblivion is also described as manifesting all possibilities which sounds awfully like alternate realities. During dragon breaks and other such shenanigans the only things that are said to consistently remain the same are the planes of the Gods which suggest they exist above them.
Four different points, one not as reliable as the others and another a bit weird, each alone capable of making an upgrade. Now, you said this would make the humans higher dimensional too. Firstly, there are no humans in TES: TES works on the idea of sub-gradiences, everything is connected, from the Godhead at the top to the lowest of mortals at the bottom. Everything is just a small part of the entity or force directly above it. Now, why don't I think the mortals are higher dimensional physically? Well the sources on strange angles only mentions
spirits being able to do this, Hyperagonal is only used in reference to Daedra and the time dimensions are restricted to the Scrolls. I think mortals are physically restricted to the normal dimensions, but magic itself is described as hyperagonal and mortals are said to be able to train their hyperagonal senses. I mean it's hypothesized that our (real) universe may have higher dimensions, that doesn't make humans higher dimensional beings, clearly these dimensions would be locked off to us, the same is true here imo.
Taking all of this together is why I went with the upgrade to High 2-A possibly higher and at least low 1-C for Sithis and Anuiel.
Edited (added some links)