Welcome, doing the same myself. I wasn’t much of a contributor prior to the great migration and I’m trying to step up my contributions in order to help grow things.
Personally my entry into Home Assistant and Smarthome was to fix a very strange series of light switches in my house that all turned on or off different lights in 1 area and I used a series of smart switches, smart bulbs and lighting groups to make them all controlled as if they were on circuit, as the cost to do so electrically was prohibitive.
Now my automations are mostly to check on the state of the house and report problems. Such as if the door to the laundry room is left closed too long (as the litterbox is in there) and to check on the state of battery powered devices to see if batteries need replaced.
I try to keep the automations simple and unobtrusive.