from what ive seen, cocopeat is used mostly for cuttings and seeds because its great at holding water. ficuses are tropical, so they like lots of water, but peat is not good for draining. i wouldnt use more than 50% peat in any mixture, especially if you are able to water it daily. There is no magical mix, but you do want good drainage, some sort of coarse material that allows water to freely flow through and out of the pot, which brings air to the roots.