Well, their kind was self-designed to rule over all the rest. And what they have at their disposal is but a fraction of Soul Alchemy, which all the ancients are said to posess naturally. Fighting pattern has a lot of similarities too, so I don't see any reason to put Aselian lore above The WORLD's one.
1) He really has never revealed his child (real) form, nor Eternal Sword ("created" for Duke to wield originally and the source of his eternal youth), but he is talking about his sister & descrimination wars, so no doubt here (and no wonder everyone are scared of even half bloods to death up to date).
2) Another project like Veratropa at the beginning of some another world sure is not impossible, BUT it wouldn't be identical, because of Jildia adsorbed and Niata supervising & sharing Pasca's knowledge with ancients, who built Veratropa to preserve the Terminal in the first place.
3) Mint, Mithos, Dhaos & Duke are those who wield time-manitupulating magic on the open, btw... and source of Mint's power on Aselia is the Yuggdrasill World Tree.
4) There still can be quite a number of landmines about how to fit Devic Era in this, but... one step at time, I guess.
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