You seem to prefer to keep the whole system alive but want to save uneccessary power usage.
Hibernate is an option but some on this forum have trouble in resurrection.
I use settings which never turn off the HD, nor let the system go to standby.
The monitor turns off after 20 minutes but can be revived with a squiggle from the mouse.
These days the monitor uses far less than the old CRT. so the saving will be small.
Then I do switch off at the wall overnight
Also if I know I shall be out of the house for more than a couple of hours I will shut the computer down leaving the router running and power still on at the wall.