Can delete a UV Map / Texture, via
bpy.ops.mesh.uv_texture_remove()
But how can I delete a UV Map by it's Index?
Set the active index,
Similarly to materials and other lists where the active and active index can be set.
Example in python console. The 3rd UV map is active
>>> C.object.data.uv_layers.active_index
2
Change instead to second (index 1)
>>> C.object.data.uv_layers.active_index = 1
Operator removes the active UV map
>>> bpy.ops.mesh.uv_texture_remove()
{'FINISHED'}
See also How to find and delete extra UV layers on many objects? : can remove directly using the remove API method.
>>> C.object.data.uv_layers.remove(C.object.data.uv_layers[1])