The desert building should not use oak, they should use thing like smooth sandstone or sandstone itself.

You're right. Currrently I do not have any code that substitutes in different planks depending on biome, though I'd like to do that in the future.

You're right. Currrently I do not have any code that substitutes in different planks depending on biome, though I'd like to do that in the future.

Maybe you can take a look at this datapack? The developer of that mod change block based on village theme but only affect their new added village. The same way can be done on Bountiful side on vanilla village.
https://www.curseforge.com/minecraft/texture-packs/repurposed-structures-bountiful-datapack-compat