Also it seems like the Ethos is written/provided by the [Rapid Iterator] Entity/Spirit, not Aboleath. The clawing and biting and screaming and feeding and remakeing and feasting gives the blurb a predator-prey/untamed-wilds theming.
[Form Fracture], [Dissolution of the Self] and our {Boundless Ethos} skill were almost assuredly all provided by Colossi/one of Colossi's sublets, which is probably also the entity we met outside of Harmuph. I'd bet that the attack it used against us is also what caused [Dissolution of the Self] to be among the offered Ethos picks. The [Rapid Iterator] being one of the things that sublet corrupted I'd bet.
I don't think that this is related to the Second Integration stage goal though. Colossi's arrival is probably what caused the 7th Era to begin, as it's not interested in what the Angels and Demons were busy doing before, but only in destroying and eating everything.
Also: while we're on the topic, idk if this has been mentioned before, but I noticed this when looking at the Foundational Ethos list recently:
[Library of Achievement | 5034-CD, Ancient Recaller] (Foundational): (Concordance/Legend)
[...]
Provided Feats should only be tied to those of us more than half integrated, to prevent application instability.
I suspect that Integration Vectors might not just be something a Weaver creates and then sends out, but something that is part of its Weaver, and by anchoring them into the souls of humans in the Melange Layer, they anchor themselves in the Melange Layer. My guess would be that they're trying to do what Yarlsfreet and Pithe did, but on a scale that allows a lot more of them to do so. Currently however human souls are too weak and brittle to contain much of the enormity of the Weavers' existence, which is why they're trying to up the strength of human souls and make 2nd Integration Stages widespread.
If everyone's angling to get as much of themself into the Melange Layer as possible, that also explains why the worst punishment that they could face would be to get identity-wiped and have their Integration Vectors put at the back of the queue:
[Championed Uplift | 0000-A, 2nd Integration Stage Initializer] (Foundational): (Legend)
Tailored placement; should be attuned only to one identified Premium Integrator at a time. Provided identity fracture trials do not result in a decohered subject, the sponsored Integration Vector can have its layer-limiters removed. Weavers are reminded that inducing Melange bleedthrough on a subject who has failed their trials may irretrievably scatter your Divinity, the trials are there by definition to test compatibility before the fact. We have patched most loopholes and if we catch you, you'll be Identity-Wiped at best (all your Vectors will also be moved to the back of the queues when you reincorporate.). Current projections before widespread 2nd Stage Initialisations can be reliably applied without prior testing; fourteen Millennia.
Considering that, [Championed Uplift]'s purpose would be to identify humans that are suitable to have a larger presence of the Weaver integrated into their soul (I'd expect that's what Melange Bleedthrough refers to) after they've passed the identity fracture trial (presumably identity fracture happens/is necessary to allow melange bleedthrough to happen).
Considering that we know that a soul resembles the melange layer, maybe having the layer-limiters removed would allow a Weaver to do the same thing Yarlsfreet did, but on the scale of a soul instead of the entire plane? That'd integrate them so thoroughly with the person they'd maybe become a new source type for that person that only they can access?
Also sidenote: from Mindstate!Lilly we know that Marcus is scheduled for a Premium Allocation when he receives his Ethos, so presumably he'd be eligible for this.