New plugin I wish to share with others: adminBranding.
adminBranding is a plugin for Zenphoto CMS for customization of Admin backend.
Originally adminBranding was intended as a fork of zp-branding v1.4 to be merged with zp-branding.
Since our approaches to the task and customization needs are so different, me and @fretzl have decided to keep projects separate, hence the rename. Calling it zp-branding (kuzzzma version) potentially could lead to confusion and, anyway, I'm not Taylor Swift.
Instead of proposed zp-branding ver 2.0 this work is therefore released as adminBranding v1.0 and will be updated if need be by myself.
It was tested with latest Zenphoto version 1.6.3a.
Feedback is welcome.
Links: https://github.com/kuz-z-zma/adminBranding
adminBranding options and their effect

New version of my plugin for Admin section customization - added option to use custom CSS file in addition to inline CSS.
This allows for some very dramatic customizations of the Zenphoto Admin section + offers user a convenience of adjusting settings from the comfort of their preferred CSS editor.
https://github.com/kuz-z-zma/adminBranding
https://www.blog.private-universe.net/web-and-tech/zenphoto-plugin-adminbranding/

Great, any plugin+update is welcome.
Just to note for users, if asking for support disable any customisations because we will not cover those and refer to the standard.
@kuzzzma: Please don't embed external images or other sources directly, only link to them.