Is Cilan the New Brock? or Maybe Iris?

Is Cilan the New Brock? Maybe?

By this I Mean will Cilan do what Brock did and Travel with Ash for Many Years to Come
Throughout the 6th Generation of Anime (Which is not to far away now that the games are anounced)

Or Maybe Iris will Travel with Ash for Many Years to Come Instead

I don't know, I still want to see Brock return.