Looking to add a nakiri to the mix, been most interested in the Munetoshi, Toyama, or Kochi's at 180mm, or possibly 210 for the Toyama. Let me know if you have one and are looking to sell.
The Toyama 210 is definitely worth considering if you like heavier knives. It can do everything that a 180 can but may feel less nimble. I personally prefer the 210 size over a 180, but I also like cleavers!
I would only add that difference between a 165 (ca 150g) and 180 (200g) nakiri is very significant. 210 will be a monster that will be hard to use for fast chopping and will probably require different cutting technique.
Yeah I think the 180 would be about perfect. The 210 Toyama just sounds awesome though. I have a Shiro Kamo 240 k-tip that feels like a huge nakiri, it's awesome but I think it would be more wieldy if it was shorter.
I also stumbled across some Wakui nakiri's that look nice, on Japan Messer Shop. I'm not sure they ship to US though, anyone know? When I made an account, the shipping country defaulted to Switzerland when I tried to select US. Emailed them but haven't heard back just yet.