Not using Z lenses sounds like people that buy a Jeep Wrangler only for pavement, never dirt. It's just not right.
I bought the Z6 for its features alone and not on the strength of its lenses. I have a nice collection of (all nikon) modern glass so i am holding on until the price of their equivalents is more realistic. I must admit though, that i am drawn to the 14-30 f4 as a replacement for my 16-35 which i have had since that model was first introduced.