W10 System Image vs. Files Bkup?


I do run a cmd that backs up my user files via “copy”, but I also use W10 to create a System Image on an extra HD that is inside my PC’s tower. I used to bkup the system image to my WD MyBook external HD, but when that bkup started running in 1/10 of the time (or faster) it had always taken before, I assumed the external drive was causing a problem even though the bkups ended with no error msgs of any kind. If I had been out of the room when the bkup ended I would not have known the System Image bkup was no good.
System Image backups to the 2nd internal HD run a normal amount of time. I do occasionally send a System Image bkup to a portable WD external HD, btw.
So my question… If I tried to restore my PC using a reinstall of Windows and restore of my personal files and reinstall of my applications (like MS Outlook 2007, etc.) files as HTG recommends, wouldn’t my personal settings of my apps be all wrong compared with right before the crash? For example, I have my MS Outlook 2007 set to use a certain filename for the main email file and it probably is not outlook.pst. And every so many times I shut down Outlook it automatically runs outlook backup that backs up specific filenames of the main .pst file and 2 different archive filenames. In other words, wouldn’t following HTG recommendation (as above) make the crash recovery a pretty miserable experience? I am not a techie.