
but regardless, that's nowhere near a "complete introduction" to particles. I have a textbook (The Structure of the Japanese Language by Susumu Kuno) that devotes three entire chapters only to は vs. が. Of course, you can give a tl;dr of it, ignoring edge cases, but you do have to at least talk a bit more carefully about what a topic is, and what a subject is.
I'm currently reading The Structure of the Japanese Language, and that is indeed the case (the book doesn't use kana, maybe it was difficult to typeset at that time). And I'm not at all proficient with the language at this point, nor have I studied kana specifically. I've struggled a lot with it initially, but consistently refused to read or write romaji, which may have helped.
(Having just recently returned to the RTK deck after a break, I feel it's not enough and I probably should be working through words or sentences already, maybe in parallel. Thank you for describing the various aspects of your workflow in this thread!)