update!
So I've been cross training Xing Yi (and Bagua) now with the same friend for close to a year and I've definitely come to have more of an understanding of the answers to the questions i've asked in the past. At this point, I have a better understanding of the 5 elements and have been training what's called an "Advance-Retreat Linking Form," though I'm not sure if that's the actual "linking form," but when i compare it with forms I see online, there are many similarities and differences so i cant really make a conclusion on that matter.
In addition to this, I've also been occasionally training a movement called "squatting monkey" which has helped me understand a lot about the full body movement in the elements. I think the Xing Yi I'm learning can best be described as a combination of Shanxi Che Xing Yi, Dai Xin Yi, and Xin Yi Dao. Honestly, I'm not sure where exactly the "forms" i know are from out of this group of systems.
For anyone who reads this thread wondering about the same things I mentioned in the OP, here's a list of what I've learned over time:
1. Like many mentioned, the 5 elements are more about different "roads" to use your energy (i actually didn't really understand this when others mentioned it, but i do understand more now and I'm sure there's a lot to go). I'm still a newbie, so the easiest way I could explain it in an example is that the way the body expresses it's energy through something like Pao Chuan from start to finish covers different angles and directions than the other elements. In delivering mass, I realized this could refer to how one delivers his own mass/body as well as taking in, nullifying, and sending back another person's mass.
2. At least as far as the advance-retreat linking form that I learned goes, it's not simply different combinations of elements but rather the concepts of the elements expressed while moving back/forth/diagonally/etc. Also, it's like the movements contain circles that are non stop from the beginning of the form to the end.
All in all, xing yi is a wonderful and effective art, and one that I'm very glad to be cross training in
Everybody wants to go to heaven but nobody wants to die...