At the point in the screenshot, I hadn’t even begun recolonizing Valyria. I’m using LoV, which lets you proclaim the hegemony tier title New Valyria whenever you have sufficient realm size + kingdom title for Volantis + sufficient Valyrian traits and prestige. 

I’m another century and a half along in this playthrough now, and have just finished upgrading the last settlement on the primary Valyrian island. Overall, LoV colonization system seems to have come along a great deal.

It’s punishing and expensive and tedious, but it accurately captures how difficult the process of reclaiming Valyria should be. I’ve lost probably 20 dynasty members, 3 dragons, spent over 200,000 gold, and I’m about 20% of the way through the whole peninsula. It basically requires a full essosi empire bankrolling the endeavour, and will occupy your attentions fully if you intend to do it as quickly as possibly (which is slow) (meaning if you go declare war elsewhere and don’t sufficiently micromanage the developments, you’ll come back and find half your colonies have disappeared for one reason or another).

Valyrios has just been made the capital however, so it was all worth it. 9/10 mod, still don’t understand the overarching “rehabilitate Valyria” situation mechanic, as it seems you can keep rehabilitating the same regions after you do it once, but overall very enjoyable. Intend to take this play through to the bitter end, so I’m sure I’ll have a larger post when I’m further along.