thanks for all the feedback (good and bad, we appreciate both).
Indeed the admin is not as customizable as it was in v3 largely because we are investing in making it easier through programmatic APIs and not through the legacy file override system which was easy to start but difficult to maintain long term.
We started with the few injection zones that plugins can leverage and really want to expand that system even further. But we needed to keep maintainability in mind and for many of the improvements we wanted to make around how we build the admin panel with all the plugins we couldn’t maintain the file override system anymore.
For those unaware though you can customize any part of Strapi, including the core using something like patch-package (it’s really easy, even easier than our v3 extensions system was). Downside is admin customization, it’s not really possible/easy to setup the auto-reload with the --watch-admin flag