ADB Backup Question

Has anyone used ADB to do a full backup of XT1575 and subsequent restore? I want to do a complete backup of phone so that restoring EVERYTHING to exactly as it was, after factory wipe (or with a new replacement phone), would be a simple matter of restoring from complete backup. Similar to what you get with the old Norton Ghost for Windows PCs: Brute force, image, 100% backup and restore, the restore puts the device back in exactly the same place it was when backed up including OS, config, apps, everything.

ADB:

I noticed that ADB backup of XT1575 (command "adb backup -all") produces a backup file about 25MB in size. This is whether the phone is encrypted or not. That seems WAY too small to be a complete "full image" backup of the phone, I would expect several GB. (For comparison, a different Android 5.1 phone produces a 200-700MB backup file, using the same command "adb backup -all".)

Running the command "adb backup -apk -all" produces a huge multi-GB backup file - even larger than I would expect for the OS/config/apps image itself. Is this the "full image" sort of backup I want? The ADB documentation says the -apk switch backs up apk's, which I believe should not be necessary to back up the installed/compiled apps as part of the system, which are different from their respective apk's. But without the -apk switch, the ADB backup file is only 25MB.

Appreciate any info offered.

TIA...