You gonna call 'em out on holding back like that?

That's not a joke. Out of 4 classes between them, I only see one casting class and it's a list-caster drawing from a less than stellar list. Don't get me wrong, they're interesting characters, but they're not balls-to-the-wall power-houses like I'd expect when presented with the phrase "all-out."

In answer to your question, No. I've never DM'ed anything like that. Probably won't either. I don't care for gestalt and I'm honestly not sure I can suspend my disbelief high enough for such a large template stack to have clearance.

Good luck with that though.