I'm biased of course, but if you want a different route, you could go with a CADE 1200 or 1500 in those dimensions. The side doors and integrated ATO have been pretty nice to work with. Only downside I've had is no Eurobrace to hold tools etc. but you can probably add one. Tariffs hit them hard...
That's weird, mine works fine during my feed mode and water change mode. There's a 5 minute delay for turning the skimmer back on and a 30s delay for turning my return back on in case I accidentally change modes. I've never had an overflow with the skimmer on a controlled outlet.
The airstones should be enough for most of the day next time. Don't worry about running the heater since it's not going to matter during summer and lower temps actually increase oxygen solubility.
Try power cycling them to see how they behave since that's often their failure point. In general you need to test all your systems to see how they react in a power outage and if they return to previous settings or that your sump doesn't overflow.
Might be something @Srt4eric could print out, there's got to be a file out there.
The Kessil looks 10x better plus you won't worry about those strips corroding any more.