I had a talk with Eyal 4 weeks ago about this and wondering if you guys can show this to him if he already didn't looked at it.
I just did an update to my github account with the code styling changes you made in 1.2. See https://github.com/markoheijnen/types/compare/use-hook-add_meta_boxes.
I just fixed the merge conflicts but everything still seems to work fine.
Best regards,
Marko Heijnen