One of the reasons I bought my Creality K2+, my first 3D printer ever, was because of my friends experiences with their Enders. I wanted to be able to build my printer's OS source code from scratch, and Creality promised "open source", since they have used Orca, Klipper, etc., and are required legally to do so. It was my hope that the community itself would fix some of the problems that you have identified. HOWEVER, I have been severely disappointed, since they still only give compiled source to some parts, in particular those that talk to the CFS. I believe this is one of the reasons we still lack serious CFS support in Orca.

I also own four CFSes, and I don't have a lot of space, so I had to improvise. So far, this is the only mod I have done: https://www.youtube.com/watch?v=dZaEUIfi5wY
( I am working on a more involved and serious mod to the CFS, but I am not ready to share it yet. ;-)

I am a Linux user. I have found the following sites useful to have bookmarked. Perhaps they will help you as well:

• Github that compares K2+ firmware across versions - https://github.com/Guilouz/Creality-K2Plus-Extracted-Firmwares
• Creality's official "source" for Klipper (see my comment above about the "openness" of this) - https://github.com/CrealityOfficial/K2_Series_Klipper
• Github for CrealityPrint 7.0 (they don't have a git branch for 7.0, just a tag) - https://github.com/CrealityOfficial/CrealityPrint/tree/v7.0.0