I love my MacBook and cannot imagine living with an iPad, my wife lovers her iPad and cannot imagine living with a MacBook, and we both use the family 27-inch iMac for graphics work. The differences in our preferences are the work we do and how we do it.
Your non-techie friend’s ability to get by for nearly a year with an iPhone while her iMac lives unused in the basement says a lot about her work flow and device needs. Explore with her the things she does and would like to do that her iPhone cannot.
Following are a few random observations.
My wife finds the 27-inch iMac tires her eyes after about 90 minutes whereas she is comfortable using her 11-inch iPad Air all day long.
Touch ID is finicky for seniors with dry skin and worn fingerprints. If this matters, make sure it works well for your friend. If face ID is necessary, then iPad Pro may make sense.
While I prefer my MacBook keyboard, my wife likes her iPad’s on screen keyboard and has no interest in an add-on keyboard.
Dave’s reminder to obtain adequate storage is spot on. Consider how much storage she is using on both her iPhone and iMac.
I recently upgraded from an old 13-inch to a new 15-inch MacBook Air and love the larger screen for multiple windows. My wife finds multiple screens on iPad are confusing and would not consider a 13-inch iPad, it is too bulky.
Given the speed with which Apple operating systems are evolving and demanding more resources, my suggestion would be to prefer an M series iPad over the basic A14 model.
I don’t know how I would use an Apple pencil, but it looks very intriguing.
When shopping consider the ergonomics of the show-room. Usually, they have desk-like settings, but no armchairs or sofas. Consider where your friend likes to work.
That said, enjoy your time together and device shopping.