Conditional Highlighting is a great feature, but I don’t like the built-in styles. I know I can always copy from one of my existing tables or templates where I’ve created Custom styles, but it would be nice to change the default styles for the app. The same goes for shape and chart styles. Is there any way to change the defaults?
I would like to avoid constantly having to make the same changes to various elements on various spreadsheets.
Device: Mac Running Monterey
Yes. Just create a document to serve as your Numbers template. Then use that template when you start a new document.
So set up the template just as you like it. Maybe with an empty sheet, or maybe with a single table that can be easily deleted or used, whichever you need depending on the new document you create. Set up the styles as you like.
Then choose File, Save as Template. Then pick Add To Template Chooser.
Now you can choose that template whenever you start a new document. You can even go into Numbers, Preferences, General and set that template as your default one.