Easing into thinking about things like this seems to be the best method, because you cannot dive into complex situations without a good foundation; you don't do calculus without arithmetic.

Yes. This is tricky, because as mentioned above, these ideas stretch into antiquity, and so some of the sources have a degree of obscurity or the textual origins are even lost (in part because some of these older forms of religious expression were conveyed orally and not recorded in language, according to some scholars). This is a metaphysics, after the supernatural, of something universal and eternal that doesn't change, an absolute that is 'stepped down' and expressed through symbols and concepts we can understand, draped and drenched as we are in relativity and dualities.

There is a 'space' here where Baha'i meets concepts that are integral to what is known as the Primordial tradition or Perennialism (the religious philosophical kind. Interestingly the Wikipedia entry mentions Baha'i), but after the religious relativism espoused by Baha'u'llah are garbed in different forms in Baha'i. It can be difficult to keep ones 'head' and focus so to speak when wading and wandering through the landscape of this terrain. There are different sources one can got to, to find foundational concepts towards orientation and understanding. Some of this is Baha'i, some not strictly in name but is still dealing in the same, universal territory.

This is where the universality of religion(s) exists conceptually, intellectually (which really, only allude, necessarily symbolically, to ontological conditions and structures). I've been looking into this area for awhile now and I still feel like I'm only grasping the edge of something as massive as a large mountain.

This appears to be a 'one thing' that is interlinked.. is this the 'ancient wisdom' that Baha'u'llah regularly makes reference to?