My perspective:
First: About the Cemeteries/Catacombs/et cetera: The only hold such a city would have would have been predicated on its history, and a physical body is a more symbolic representation of the people whose contributions keep the city going. If Oasis were to have survived the apocalypse, it would need every form of symbolism it could get; people need as much inspiration to keep going, and being forever remembered would assist with that.
About Religion: Religion can act as a bonding force, bringing together people who would otherwise be opposed. If the clerics at the time were to have whipped the people into a frenzy of worship, explaining their continued survival as miracles from the gods, then the city itself would have been very religious. Which isn't to say that there wouldn't have been opposition; many athiests or anti-clerics may have claimed that the apocalypse was caused by excessive worship of the gods or that the gods have forsaken the people during their time of need; depending on the success of the clerics preaching, such doomsayers/naysayers would be drowned out; people intrinsically wish to feel part of a group, and a church is a very encouraging thing to band around. In fact, such a church may not even be lead by clerics at all; if the church is seeking power for itself, it would very likely get away with it because the gods could not afford to lose followers and by extension their foothold in the city.
About +1 Clothing: Why can't Clothing be enchanted? I see nothing that specifically says it can't; while Magic Vestments might state a line that Clothing is treated as armour with an AC bonus of +0, Robes (which are also not armour) do have an exception in the Robes of the Archmagi, which provides a +5 armour bonus. This isn't an attempt at gaming the system; Bracers of Armour are most certainly more effective and would be equivalent in cost, but would not look nearly as symbolic on a character who is going for symbolism (he has 4 skeleton Butlers, while dressed as a courtier (such as someone might when hoping and having the means to become a noble.)