Late to the topic, but here's my rundown:
12-50mm: Don't care for it. Not wide enough for wide work, not close enough for macro work. If you want to be able to access macro on the go, you have an absurdly expensive zoom gear & port to buy. Image quality isn't that great. Will fit into the 60mm macro port with a basic zoom gear or using the electronic zoom (i.e. no macro function). Didn't spend much on the lens and nothing on an additional port or zoom gear, so I'll keep it around as backup or as a loaner.
9-18mm: Not wide enough for most WA photos, smeared corners for days. Better for medium sized animal photos than anything else it does. Uses the same gear and ports as the 14-42mm. Sold it off as quick as I could.
Panasonic 7-14mm: Almost wide enough for CFWA. Nice and sharp, not crazy expensive. Long end isn't great for medium animals such as sharks that like to keep their distance. Issues topside with purple flares when shooting towards the sun. Stays in the bag.
60mm Macro: Amazing lens. Easily my favorite. Definite buy, especially since it goes on sale for $300 occasionally. Stays on the camera 90% of the time.
Olympus 8mm Fisheye: Really wide. Great for CFWA. Nice and sharp. Pricey, but I got my copy for about the same price as a used Panasonic 8mm, so a great deal. Haven't gotten to use it much yet though.
If you have to pick 1 lens, then get a 12-40mm and a wet macro and wet wide lens. Pick 2, then get the 60mm macro and one of the 8mm fisheyes. 3, then add a rectlinear zoom (but not the 9-18mm).
Edited by JMartel, 03 July 2018 - 06:24 AM.