Backup strategy for Laptop

[jardster]

So, I will be replacing my wife's 2019 iMac with a new MBA, because she really wants to be able to walk around the house and use the computer in different places. I am going to put a monitor where the iMac is currently and have a dock with all of the things she would want if she wants to sit at a bigger screen (all connected via USBC).

I have the same setup at home and work for my MBP, and I have a backup drive connected to the dock, but I am good about ejecting the drive each time I unplug my computer... I know she will not do that.

So, what would be the best strategy for backup? She currently has a HD attached and uses Time Machine, which has always worked well for us.

Thanks!