@Adahm
I have the same type of macros that I use when cleaning the tank and they work well with wait times before having certain equipment kick on. I have thought about this for sometime in regards to timers and power outages, for the timers I have additional timers that just keep turning things off when outside of the range I want it on, that way dosers don't come back on dosing etc. But for ATO and skimmer there are not many options. On option that you can do right now is to dial in your ATO and if it pumps outside of the expected range it gets turned off. So in the case of a power outage it comes back on starts pumping but hits 30s and then gets shut off. The one problem with that configuration at least in 4.x (I have not kicked the tires with 5.x to know if they have additional options) is you will have to manually enable it, the other issue is you could have nuisances turn offs if you tune it to low. I like that option if I had a way to automatically set a timer for it to re-enable, say try again in 5min or some configurable option. The flow would be ATO kicks off over a high value gets shut off, timer hold starts to run for set time, once timer expires it re-enables the ATO and it runs, if under run time value it continues to operate etc.
The other option that is not available through the gui but may be available via API ( I have not looked) would be some kind of a cron job that continually runs and looks at the uptime of the system, or if the rpi is on UPS looks for the uptime of some reliable network device to signify power outage. Based on that event you could disable the equipment that you want and re-enable after a period of time. Not sure if you have control via API for individual equipment via API and would require scripting outside of reefpi.
Something else that I just thought of and may be possible today would be to monitor the energy usage of the retyurn pump if it is on a Kasa strip. If the device is on a kasa strip you could use power monitoring to trigger a macro etc that would put those devices in timeout. I am just thinking of this so would need testing etc, but if you have the RPI on an UPS it will see the drop in energy for the return pump and you could trigger something based on the lower and upper values. I will think about that one some more since it may be the most viable option right now if you are running Kasa strips and your return pump is on one. You use the PH function for the energy monitoring portion.
Here is the screen shot of my return pump usage, each dip shows when power was lost doing a water change.
Some things to think about, I agree though would be nice to have something for when your not around for power outages.