
So David creates the Xenomorph... The Deacon exists before. The "Deacon Mural" in Prometheus... Did David see it, then model the Xeno from it's lifecycle? We can see something similar to Facehuggers in the mural... But are they just smaller representations of the Trilobite? In order to fit in the mural?... And maybe David is aware of the happenings between Shaw / Engineer / Trilobite / Deacon on the escape shuttle on LV-223... Being that he is virtually wired into Weyland / Weyland-Yutani... And realizes that form of lifecycle is tangible...
Then are the "puffball" spores which infect some of the Covenant crew also some of David's creations? Leading to Neomorph births? Maybe they were the first round of later experiments created to destroy any remaining Engineer/Humanoids on the planet around the area...
Or am I missing something? Just trying to make sense of the Deacon Mural - David's Xenomorph connection/flaw...

I thought it was depicting a Xenomorph on the mural?
Well we know from Ridley Scott that David did in fact created the Xenomorph.

But what about spores? Why do you need to create eggs and xenomorph if there are already mushrooms with neomorph spores? Neomorphs even look smarter and scarier. Xenomorphs look completely useless creatures in A:C, like reduced version of neomorphs

It seems it is easier to kill a Neomorph than Xenomorph, as the latter has acid blood. Also Xenomorph involves Shaw component, which is meaningful to David.

No, the mural more accurately depicts a Deacon rather than a Xenomorph.