Where do you think Daeron I got his martial spirit and supreme self-confidence? Was he just a born military prodigy or do you think he had a specific tutor/master-of-arms who shaped him into a fourteen-year-old boy conqueror? His father Aegon III seems like he would have been too reserved/depressed/brooding to be a confident warrior (though Daena was said to idolize her father). Perhaps from Oakenfist or Uncle Viserys, even though they were more cautious about trying to conquer Dorne?

We don’t have much information about Daeron’s youth, so it’s hard to say. But the Oakenfist seems to have best fit the bill as a mentor figure – he was a good thirty years older than Daeron, already a storied (and daring) naval commander, and was heavily involved in Daeron’s planning for his Conquest of Dorne. 

But given his extreme youth at the time of his great victories, I think we have to assume that he was a prodigy, because an average student even of a great teacher wouldn’t have been able to do what he did in the time he had. 

Do think Dorne could have be incorporated into the realm without the Conquest successfully? Daeron was unmarried and had three sisters, a double marriage united the Seven Kingdoms in one timeline why not another?

Oh, you mean Daeron I. Interesting. Part of the issue there is that Aegon’s First Dornish War had some really profound path dependency issues – the Dornish aren’t going to forget their kingdom ravaged by dragonfire, the Reachermen aren’t going to forget their kinsmen slaughtered in the sands or the raid on Oldtown, the Stormlanders aren’t going to forget their kinsmen mutilated after a prisoner exchange or the burning of the rainwood. 

Also, Daeron I desperately needed a big military project to unite the realm and restore the authority of the monarchy after the Dance and the False Spring. While he’d probably have an easier time selling such a pact than Baelor and Daeron II did, thanks to not being murdered under a peace banner, bringing Dorne into the realm peaceably doesn’t quite solve the problem. 

It’s actually quite reminiscent of Edward III’s position when he took the throne of England – recent civil wars, a king deposed and then murdered (although for Aegon II they didn’t bother with the deposing), defeats abroad, a long period of regency, etc. Hence the idea of claiming the Throne of France as a way to get the barons on-side with the lure of French territories. 

So maybe Daeron I could have looked east? Stepstones are a bit meh, but maybe a holy war to reclaim Andalos for the Faith of the Seven? That might have done the trick.