Really good and useful request.
Regarding accidental data loss: Checkvist Pro account gives you up to 10 daily backups of all your lists. Not the same, but may help in some cases.Rainer Schütz commented
Yes please! I just accidentally deleted two long lists, didn't realize it for a while and then couldn't get it back :(Rainer Schütz supported this idea ·Rainer Schütz commented