As a two months newbie in smart home systems, Maybe it’s too early to share topics in this category, But i would like to show my modest project,
I am new to this field, so i focused on creating automations that depends on static data such as time, sun, weather etc… or by exploit sensors are already present in smart devices i have,
let’s start with lighting, instead of replacing traditional wall switches with smart switches, I added smart zigbee control from tuya (mini type) that fits behind the main switches, by this way i kept all switches and sockets in same style and reduce the cost,
From here I was able to control lights and make automations that turn on/off exterior light depends on sun and turn on/off interior lights in specific times, also set timer to turn off bathroom light and discharge fan after period of time
I took the advice of the members here and didn’t buy tuya get way because it’s locked, instead i bought sonoff zigbee bridge and tasmotized it then i integrated the devices via ZHA,
The next step was to convert electric water heater to smart by sonoff TH-16, I kept the traditional thermostat in place and just raised set temp to max, by this way thermostat will prevent water temperature from overheating in case HA failure, then i tasmotized TH-16 and integrated it via Mqtt,
from TH-16 temp sensor, switch and weather temp, i create thermostat and automation that set thermostat target temp and turn on/off it depending on climate temp from wather card
Because I live in an area that prone to dust storms, i used windy dust map as a sensor to close windows shutters when dust ratio exceeds 200ug/m3 and control interior light in heavy cloudy days
also because i live in country suffering from a power outage, I installed sonoff pow r3 with relay shorted and tasmotized it then i used it voltage and current sensor in automation that control louds and turn off overloads in order of priority when aux generator works, i also benefited from Lg smart A/C, it’s provide full control and power usage, temp and humidity sensor for this, i didn’t need to install climate sensors in the rooms
last but not least, I benefited a lot from mobile tracking via owntracks, through it i was able to make a lot of interesting automations like open driveway gate when i reached home zone and turn on interance lights in night, also turn off bedroom ac etc…
you are right, also the pow r3 is a physical sensor, but even without those sensors there is a lot of automations ideas can be done