This entire thread has me squinting my eyes very intensely.
Even though objects cannot have a sphere association outside of being the generated divine metal, it still somehow affects them in trade. The only thing i can think of is the hides of animals, which could probably be shown by having a [ANIMAL] entity arguement to have something with a sphere (a fire salamander or domestic fire imp) they prefer and one they do not (a water sphere creature) then compare them at a later stage.
I haven't seen any proof that dwarves over-charge for minerals or alter their goods, though POSSIBLY it affects their interest in metal weapons in the trade agreements.
To the OPIn 47.04 with the corrections to religions, fixed pantheon gods should work just fine and additional ones are rare/uncommon. Clowns have their own external tag of [RULER_SPREADS_EVIL_SPHERES] or something like (i forget specific wording) that will make them generate that added with the implementation of 47.01's changes to evil biomes.
- Just adding a higher proportion to the naturally evil areas dubbed 'primordial evil' by toady in advanced or file worldgen settings may help for your own needs, supplimenting your own maps with your modifications is a very helpful accessory
However if its sufficiently evil enough, giving a dark fortress a correlating evil pantheon may co-ordinate the clown-leader into representing the one you want i think from my memory of using pantheons & clowns in 44.12 . OR by deleting the clown-types from worldgen and inserting your own [UNIQUE_DEMON], create subtypes of the entity civilizations attuned physically and mentally representative.