The default layout is the one oriented for healers so I might as well just call it that. I've heard good feedback from other healers who use it so I don't see a reason to make a new one. I suppose the DPS layout could work for healing with minor alterations but as it stands I think there's enough in the pack for players to put together a layout that fits their taste.
That being said I'm always open to new ideas. If you have an idea for a healer layout feel free to pm me screenshots or w/e suggestions you have.