I'm researching for an American TL; I'll make it eventually, I swear!
It's just that the POD here has some, uh, pretty surprisingly broad implications. It's taken me a very long time to research this far and I'm still not done.
I'm pretty sure that judging between the sheer size and complexity of the TL, the wealth of information I've learned (from the ground up, to be honest) and the fact that I've never written a TL before ever it's either going to be Ben-Hur levels of epic or a total flop.
I think that's what plagues a lot of ancient timeline writers, actually. Pre-modern timelines are easy enough, all the history is documented and you can pick a nice tiny POD. For most ancient/medieval PoDs it's go broad or go home.