Yes indeed date selection is useful.
But as in so many things, the easy version is far less reliable.
I use at least four different approaches to settle on any date for important activity. It is not easy to teach, but is easy to do once you know
The day must not clash with month or year
The hour must not clash or have a conflicting san he relationship with the day
The date must not clash in a negative way with your bazi
Dong gong method
Reality (there are just some things that you can't do on any date you choose)
If I get these all in order, I proceed or make what compromises the real world requires
Don't despair. The situation may not be nearly as bad as you think.