My 84 year old mother does remarkably well with her suite of Apple products. However, it would be nice to simplify some things. She only calls or chats with a limited number of people. Reworking the phone and messenger apps to use large pictures of the people would be a benefit. Something similar for the camera / photos app would be great as well.
You can pin messages in iMessage, which turns it into a big photo. Also when you hit the search button in Photos it’ll show you big images of people’s faces if you want to see photos of a particular person (if you’ve trained your phone on those faces).
I do wish the “favorites” view in the phone app made the headshots big like iMessage, though.