I believe that the --debug is not necessary but your ideas are better served by improving man or info pages with good examples.
I find
date -d'+1day 14:00' #
date -d'tomorrow 14:00' #
works just fine as
date -d'14:00 today +1day' #
date -d'today +1day +14:00'
an example from crontab
#to run something on the last day of the month
#minute hr mnthday Mth DoW COMMAND
30 14 28-31 * * [ `date -d tomorrow +%d` -eq '01' ] && /local/bin/run_this.sh
Regards
Leslie
Mr. Leslie Satenstein
Montréal Québec, Canada