I'm curious, why are they arranged in triangles? Is that for Ea, Avra, and ari, or do they represent other forces?

So the purpose of an ivìr is basically to demonstrate how the soul and creation emanate from the divine. A distantly similar analogue from an Earth religion would be the ten sefirot--however, whereas sefirot are numbered and arranged in a very specific order from top to bottom and there are always ten of them, the elements in an ivìr nest inside each other and their order and composition are variable (owing in part to the hidden path in arí, which I explain later on.) To extend the comparison a little further--if, instead of watching the Ohr Ein Sof from the side and resolving it as so many sefirot in a line, you decided to ignore all the scary yellow warning signs, shove your way past the angels in hard hats, and look straight down the existential beamline--most Ru are of the opinion that you'd see some kind of ivìr. Sorry, I just watched a documentary about a particle accelerator, got synchrotrons on the brain.)

The triangular geometry arises from the nature of the script and the fact that the concept being expressed here entails a quasifractal conception of reality and creation--thus, things within things within things within things, so on without end--and hence characters being drawn within other characters to symbolize this. The compounds Éa, Avrá, and arí, and the character i all contain a as a radical, which is straight up just a triangle. So you can think of this whole thing as some funky semantic crystal being grown around a--except from the outside in and the inside out at the same time. Since the recursion is infinite, there is always an innermost a radical that can be visualized as containing another ivìr--the same or different. Likewise, the outermost character is implied to be enclosed within the innermost a radical of yet another ivìr.

Moreover, the lower-right corner of arí has a two-taloned stroke that, when enclosed by the next a radical in the recursion (that of i on the left; that of Avrá on the right) hints at the shape of another, hidden i--i has an a radical, so it represents just as valid a path as the a within the character arí itself. (This detail represents the option within life to choose a harmonious path--free will.)

Also, a itself is part of the cycle, because by itself it essentially means "thing" or "something"--the opposite of "Nothing", and is thus a necessary part in describing how something (a) arose from nothing, i.e. why things exist (according to a bunch of glorified magical seagulls, probably after smoking a lot of ichí.)

(In short: Because a is a triangle and everything else needs to fit in and around it.)

cool! Thanks for the thoughtful explanations.