I've now discovered I can edit the home screen using the website (not the app). I wasn't able to figure it out using the app, but the changes to the home screen in the web version flow through to the Android app.
I've deleted what I wrote previously because I've found a fix that works for me.
To get a useful home screen in the app and on the website, I went to the website and disabled the "in focus" option. Then I was able to add items to the "at a glance" option. I put everything I want to see on the home page into the top section - the section headed "Select up to 8 stats you want to see on your home screen". I could add stuff underneath if I wanted to, but I'd have to click through a "see all" to see them.
My home page now is not all that different to the previous version, and I think it will work for me well enough.
Hope this helps somebody else.
