I haven’t, but as someone in need of new podcasts to listen to, I’ll check it out.

Well, as @goodqueenaly has explained, it’s most likely the “Sons of the Dragon” reading (an extended bit on Aenys and Maegor cut from WOIAF). 

Given that GRRM has talked about it in a So Spake Martin, I’m going to say not fanon. 

The main difference has to do with the relative unity of the Reach, given the relative weakness of the Tyrells’ position – so you wouldn’t see the Reach splitting during the Dance or the Blackfyre Rebellions. 

But also I imagine you’d see a different relationship with the Iron Throne – whereas the Tyrells have always sought royal favor b/c of their desire for a royal marriage, the Gardeners would have been more like the Starks or the Lannisters or the Arryns. 

Sort of – it’ll be about the origins of the Hightower kingdom, the question of Valyrian trade and/or colonization, and the question of written records. 

Mike Duncan’s Rome Podcast and Revolutions podcast are both excellent.

Dan Carlin’s Hardcore History is a lot of fun.

Jaime Jeffers’ British History Podcast is quite good on everything 9th century and before (he’s still working his way through the life of Alfred the Great, so he’s got quite a bit of history to work through).

Robin Pierson’s History of Byzantium podcast was useful to me in researching the Battle of Blackwater.

Here, listen to this guy:

https://www.thebritishhistorypodcast.com/

The sources aren’t great on numbers (in part because the GHA divided at various times) and historians disagree about various estimates. The lowest I’ve seen was 1,000 men, the most common estimate is around 2-3,000, I’ve seen some say 6-8,000, and the largest estimate I’ve seen was around 10,000. 

The Faceless Men are primarily a religious organization, so they’re less concerned with profitability.

I’ll get into it more in the essay, but – it’s highly repetitious, with a lot of ultimately pointless back-and-forth conquering of one of two minor pennsulas, there’s the frequent reuse of names, the Dorne side of things is rather uninspired compared to the Reach, the Andal invasion is a bit meh for no reason whatsoever, and they just don’t do anything until the last three hundred years before Aegon’s Conquest.