Just to play devil's advocate...
I use both the Oly 9-18mm wide and the Oly 60mm macro with the Nauticam 4" wide-angle dome. I find it a good entry level set-up that gives me both wide and macro options with the same port. (BTW, both lenses are on sale now at a $200 discount at the Olympus store).
For wide angle, I add a +2 diopter to the 9-18mm lens for better corner sharpness.
For macro, I just leave the 60mm lens on full range since focus is quite fast. I also made a $10 DIY flip diopter holder for the Nauticam CMC for super macro shooting (the original one is almost $400!).
As I bonus, I was able to attach the zoom gear for the 9-18mm lens on a Rokinon 7.5mm fisheye lens. This allows me to manual focus with this lens when used with the Nauticam 4.33" dome.
Hope this helps!