IMO there is a down side for imagers backup apps as you mentioned above;
1- it creates identical size of the active partition, 64GB in my case for a 64GB SD card
2- repeated picking up and inserting the SD card can cause the connections to become loose between the card and RPi (happened in one card before to me)

So I’m using on the fly back solutions over the network called hot backup, where image is created at the size of the used space and not the entire card and I don’t have to touch the card from its place. Also I can compress the image file as in my case from 32GB to 17GB using winzip.

I wrote a script to help automate this process and I have using it successfully for more than a year now

I can share it if you are interested

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