This is really admirable stuff and I share this kind of goal even though I'm not working in APL style at this time, though I understand the appeal of shifting in that direction as more of the code gets abstract - and it necessarily should be so abstract if you're trying to maximize the simplicity. I believe most codebases suffer from prematurely abstracting with the easy stuff built in the source language(classes, generics, etc), and then not having the abstraction they really need when it's necessary, and being too tangled up to build it.
The only problem is that I don't know where to start if I wanted to study what you're doing and take notes. Those millions of lines of changes are still lurking in the background as building blocks for an overall understanding.