PowerApps Features explained? Documentation?

[SaWu]

Please be so kind as to read my full post before responding.
Thank you for your consideration.

I am aware of this blog and posts like this:
https://powerapps.microsoft.com/en-us/blog/new-cds-capabilities-for-canvas-apps-enter-preview/
Is there some kind of (more) extensive/regular/structured documentation of features that can be found in the Advanced settings of PowerApps?

In particular I want to know about the following Preview features which are already turned on by default.

1. Use GUID data types instead of strings
   How does this interact with Blank() and with Patch using a Blank() id to create a new record?
   How do I convert a guid to text for output?
2. Control property optimization
   What does this actually do? I haven't yet noticed changes in the number of properties of controls. Does it not affect the side visible by the developer of the PowerApps?

I also want to know about this experimental feature, which I have not seen take any effect yet,
Formula-level error management
It sounds very interesting, because I have had PowerApps, and apparently, the "regular formula checker" break down rather often after one minute change but PowerApps only pointing to problems in some other spot that was affected but not my last change that broke it in the first place.

[PaulD1]

There really needs to be a link beside all these feature to take you to some more detailed documentation and examples of usage.

Features suddenly appear and then you can find nothing about them (e.g. the new Enhanced SaveData Capabilities don't appear to be documented anywhere that I can find).