For `text-box-edge`
I think it's better to just call `text` as `normal` since that's what it is: do nothing—it's less confusing. I think the W3C Editors' Draft also left a note asking if `text` is a good choice. Maybe you can suggest it?
It also aligns with `text-box: normal;` shorthand.
As for `text-box-trim`, I think it's better to align it was well, instead of `none`, use `normal`. It makes sense too, `text-box-trim: normal;` = just do however the browser already handles it.
So something like:
text-box-edge: normal alphabetic;
text-box-edge: cap normal;
text-box: normal normal alphabetic;
text-box: normal ex normal;
Just a suggestion and thinking out loud.
What I can't wait for is `ideographic`. Badly needed (I think) 😅