Best way to create a simple model viewer camera

Trying to create a simple (runtime) model viewer camera. It lets you zoom, pan, and rotate around a particular model or area of interest.

Would modifying the CharacterController package camera's be overkill? Are there existing camera's for such purpose?

You could try this, http://www.unifycommunity.com/wiki/index.php?title=MouseOrbitZoom or this : http://www.unifycommunity.com/wiki/index.php?title=MouseOrbitImproved

hope this helps.