Currently when in DEBUGSCRIPTS mode only "set -x" is done.

Personally I prefer "set -vx" when debugging bash scripts because
'-v' prints the script source code lines (in chunks as read by bash) and afterwards '-x' prints the commands and their arguments as they are executed.

For me this makes debugging issuse very much faster because I see first the original source code lines and then what commands and arguments the bash eveluation results which helps me very much to understand what is actually happening.

Hereby I request that in DEBUGSCRIPTS mode "set -vx" is done.

I propose the following in usr/share/rear/lib/framework-functions.sh
(plus some explanatory comments):

function Source() {
...
    # in DEBUGSCRIPTS mode print shell input lines as they are read
    # and print commands and their arguments as they are executed:
    test "$DEBUGSCRIPTS" && set -vx
    # the actual work (source the source file):
    Debug "Begin sourcing '$source_file'"
    . "$source_file"
    Debug "End sourcing '$source_file'"
    # undo DEBUGSCRIPTS mode settings:
    test "$DEBUGSCRIPTS" && set +vx

If you like it, I make a pull request.