Try out ncvp theme
Even after inhibiting the loading of a lot of block stuff on each page, site looks quite good. In particular, Home page works, although the styling of the list of posts may be a bit lacking.
Tag: url
Source of media files
Move images and other media files which have to be loaded by URL to the cloud so the URLs don't have to be fiddled with as the site is copied around
Move away from block editor
Now it's clear that I don't need full site editing and only need the block editor for the Home and Blog pages, convert all other pages and posts to the classic editor.
Category vs Tag
Each post has only one Category. It can have various tags
Post with an image
If you don't want the image to pop out with a Fancybox effect use a gallery shortcode with link="none". To get a pop out link="file" The advantage of using single image galleries in this way is that the code is very simple and there are no urls to interfere with copying.
Force strong passwords
I'm surprised this isn't part of WP core. There are a few plugins which address the problem, at least one of which admits to being susceptible to being bypassed by a knowledgeable hacker. It ought to be possible to see how strong a user's password is from the dashboard.
Second level page
The root is level 0. We never see it. The pages in the top menu are level 1. This menu is effectively static. The menu item for this level two page appears at the extreme left of the side menu.