Oh wait... the Neutron does have a second VCA. Attenuator 1 has a CV gain control. I'm not sure if that qualifies as full VCA control. But I'm sure it'll do in a pinch.
I have two Intellijel Quad VCAs. I found them to be the most flexible due to the normalling as well as the linear to exponential response curve... and a switch to boost signal level through the VCA.
You can find other VCA modules with more VCAs per HP. But I think most of them lack features and are set at either exp. or linear response.