That is a totally different world itself (Kevlar hybdrids). Low tensions on full poly vs Low tensions on Kevlar hybrid are very different scenarios.
I happened to be a Kevlar user for a long period, and had tried all different tensions to finally settle on 15% less tension on Kevlar mains than synthetic crosses (it was not ZX that I used). But a lot of other folks seem to like high tensions on Kevlar mains and really low tensions on the ZX crosses(see the thread on ESP). I never liked high tensions on Kevlar mains. But the moment I reduced the tension on the synthetic crosses, it was giving me bad control on short angle shots. Either way I did not go below 45lb on the Kevlar mains, and Kevlars, even though stiffer than poly in theory, does not snap back quickly at low tensions (probably because of the relative string friction for the combination I used). Let me know how low tensions work for you on Kevlar/ZX. Maybe ZX being slick have a different feel/experience.
When I moved to poly world, following my Kevlar habit, at the start I used 10% lower tension poly on mains, than a synthetic crosses, and I hated it, and almost moved back to Kevlar. But then I found that for Poly it is not that bad to use full poly, and then reduce the tension on crosses, that worked for me in the poly world, and then went ahead to reduce the tensions on both mains and crosses in slight steps.
In summary, even though in theory Kevlar and Poly are stiff strings, in my experience they work in different ways, and that is probably one of the reasons why the "Kevlar world hates Poly world" and "Poly world hates the Kevlar world". I still love both worlds
.... but sticking to poly for now since I have tons of options to fill my eagerness to try new things in poly world.