A fascinating theory and analysis. To shore up your point about phylogeny a bit: it interested me that over in this thread, Seong described one of his memes in terms of panels —
I think this is intuitively quite different from the panels we see in various kinds of 4koma:
The latter examples are literally comic strips, so their heritage is pretty clear, but Seong's meme has more in common with Disapproving Drake or something like that. I think it's safe to say that there isn't really a common ancestor behind Seong's Nietzsche meme and Poptepipic, but they nevertheless are independently displaying similar features.
Beyond a merely superficial convergence, I would suggest there's a mechanical one at play here, too. I get a sense that there is something resembling cross-pollination, even, because a meme like Seong's ends up relying (to some degree) on the inherent temporality of the panel arrangement to deliver the punchline — even though earlier memes in that genre didn't really care much for this function.
My suspicion is that this sort of cross-pollination process happens frequently on the bleeding edge of memecultures. Prolific and successful memers (and memecultures) are prolific and successful, I think, by virtue of their ability to recognise, appropriate, and adapt memetic devices and forms from adjacent genera and/or species in their own work. In this capacity memes and memecultures can be kind of hypersexual,1 if their reproduction happens at a higher-than-usual rate and can transcend 'species' boundaries in a way that we typically wouldn't expect of meatspace sexual reproduction.
1 Maybe even orgiastic, if you're cynical.