I'm in the process of configuring a cloud backup for my OS X machine and am trying decide what folders to back up and whether there are any folders I should avoid.
I have complete control, by folder, over the frequency of backups, and can "seed" the backup locally (so the size of the initial backup is not an issue). My question is about (1) whether there are certain folders I want to be sure not to miss (e.g. they contain settings or history that it would be a bother to recreate) and (2) whether there are other folders that are best avoided (e.g. it is either more convenient or safer to "restore" their contents from other sources, such as a reinstall). And, as with all backups, a dimension of interest is the degree to which backing up a given file or or folder will cause frequent large backups of things that don't matter much.
Note that this is not intended as a "bootable image" backup, but rather as complete a backup as necessary for any restore other than a bootable image. Note also that I have access to all files on the machine, including hidden ones.