When you see this symbol on the approach plate, it means that either there are non-standard takeoff minimums or that there is a published departure procedure. So one way to find airports with a diverse departure is to look for ones without that symbol. It is a necessary, but not sufficient condition.
I downloaded the TPP documents for Florida and California and started looking for airports without the symbol. The only ones I found were a couple of military fields in Florida. Kansas and Nebraska are pretty flat, so I looked at the TPP NC2 plates and found KAIA.
There are no notes for this approach and none of the approaches at this airport have Alternate Takeoff Minimums symbol. If you look at the approach plate there is only one obstacle several miles away and about 1800′ above the airport. It would be hard to hit it with a standard IFR climb.
Dodge City, Harper Muni, Neodesha Muni, Platsmouth Muni, Pratt Regional, Smith Center Regional, Cessna Aircraft Field (but not the Beech Aircraft field just a few miles away) all have diverse departure assessment departures. So there aren’t a lot of them, but they aren’t unicorns.