In certain biomes (such as Red Granite), some ores are camouflaged and hard to see (such as Iron Ore). This makes it hard to find it and easier to miss. Can you make the ore textures clearer on those blocks?

Same as in real world, an ore doesn't always show up explicitly in the background mineral.
For the record, you can customize the base and overlay textures through a resource pack, same as vanilla.
Now, if you mean to change how the overlay is applied on the base texture, that's a whole different story in terms of coding and optimization...