I do this as well. I have a decent number of domains in my control, but not hundreds, so editing a text file and updating a hidden master is a perfectly reasonable workflow.
I built a ruby cli (back when Thor was a thing) that does most of the stuff, but I still edit the zone itself using vim („dns edit <zone>“ launches vim). PowerDNS has nice cli to deal with DNSSEC and bind (file) backend so I don’t have to deal with it by hand.
Of course I am the only user. But YAGNI works for me.