Most published adventures involve the heroes responding to a threat -- some move has been made by the forces of evil, and innocents must be saved, justice done, etc.
What's an adventure you might think of where the forces of light could try to gain some ground? You still need conflict and drama, otherwise there's no adventure to be had, but the good guys can take the first step instead of responding to malefaction.
Here's one to get us started:
Shifting a portion of Pandemonium:
What if some aspects of what is now known as madness could be tapped to serve righteousness? After all, prophets and oracles often seem to be divine madmen, so perhaps there is something to it as a state where the divine can communicate with mortals. The "holy fool" has immunity from lèse-majesté and thus can say (and perhaps see) what others cannot. From a physical standpoint, neurodiversity -- however an early-Renaissance setting might understand that -- can be valuable by providing different points of view, lateral thinking, or new ideas.
There is a god or two who might find such a task amenable: Dionysus, patron of maenads, and Pan, instigator of panic. These chaotic Greek deities might be willing to support an attempt at establishing an outpost on Pandemonium where the concept of divine madness could be supported until a portion of that plane shifted toward the Upper Ring -- if not all the way to Arborea, at least to Limbo. Clerics and worshipers of these gods might try to create a space where the merely damaged could be healed, and those who are not injured or cursed but only different might be appreciated.
Some tasks where adventurers might be useful: supply runs or escorting representatives from Arborea down the Great Road, through Bedlam and into the plane; defending the outpost against fiends or other natives of Pandemonium who don't wish to see part of the plane stolen; or combing the first layer of Pandemonium (a dangerous task at the best of times) for living berks, almost certainly suffering from the wind-madness, and bringing them back to the camp for treatment.
A great miracle could even be if the camp attracts Pandemonium petitioners -- desiring to become one with the plane, but only slightly evil, and willing to move *with* the area if it means that they can spend eternity somewhere other than the Lower Planes. Dionysus had a lesser-known secret mystery cult that employed themes of rebirth, giving the god an entirely different portfolio; perhaps he could actually succeed in shifting willing petitioners of Pandemonium along if a portion of the plane slid into Limbo.
And what would the result be if successful? From a metaphysical point of view, it would seize part of the concept of madness away from being viewed as wholly evil, and allow concepts like neurodiversity to gain a foothold in mortal consciousness. In order to be a good change this should be accompanied by a greater acceptance of harmlessly different ways of thinking in mortal society. This would hopefully weaken Evil on the planes in general, by reducing the conceptual territory embodied by the Lower Planes. Physically, you might produce a region of Limbo where the winds are steady, and the madness that they induce is less terrible and more mind-altering: hallucinations and visions, but not permanent, and fading after one leaves. If the region as a portion of Limbo maintained an airy nature instead of the general primordial chaos, it would be a safe oasis for travellers who were willing to pay some respect to Dionysus and Pan for the duration of a stay (and didn't mind the occasional wild vision!).