I'd say that all depends on what you are trying to do with this fine elephant. If you are going cartoony, think the likes of Dumbo .

I don't know what you plan to use this for or what look you are trying to achieve. But who says your elephant has to look like a real elephant? You could make it a cross breed, but if you are trying to convey emotion with it, why not make the eyes bigger, and give it white eyes with a black pupil or something. Big eyes allow for a larger range of motion and more visible motion.

If you are going cartoony think about the end look you want. If you want expressions you may want to exaggerate things such as the mouth, trunk, eyes, and ears.

I hope that helps good sir.