This design perfected would be as following I think. The sling being of modular construction. First, the retention cord made of a stiff/tightly braided cord that resists twisting and tangling, followed by a pouch tapered downwards from the stiffness of the retention cord towards the flexibility of the release cord. So a ''tapered'' pouch that tapers down in terms of stiffness. This would perfect it. In contrast to a Balearic sling, where the taper ends at the end of the release cord (and a very large ''belly'' of the release cord becomes defacto part of the pouch, increasing delay, friction, etc...) the taper here instead would end at the end of the pouch where it meets the release cord, and the release cord itself will not continue tapering, but instead be uniform in size, thin and flexible. (in contrast to a Balearic sling, where the release cord is wide and thick and only becomes gradually thinner towards the ''top''.)
The pouch and retention cord will last really long and can be integral or modular. The thin
release cords should be modular I think so they can be easily replaced when worn out, since this part
is exposed to the greatest wear and tear.
I am not a fan of the term ''early release''. A sling either releases the projectile ''on time'' or it releases ''late''. Slings with thick and stiff release cords and/or ''fat bellies'' will release very late compared to one with a very thin release cord.
An ''early release'' would be a fitting term for a release of the stone before one lets go of the trigger. That'd be an accident and unwanted.
So yes to what you said, the ''on time'' release is excellent, and it does make it feel more intuitive and also easier to learn for beginners.