Being on v3.0.0-alpha4 and the following alphas will get the most recent developments, including support for the HQ camera.
As you say, the HQ camera avoids the problems with colour saturation and banding in scans. It is not quite hitting some of the other image quality metrics I think.
There is a scan from HQ camera Christmas has come early! Its a new v3 server alpha release - #2 by adamglia. To get HQ working and to understand some of the limitations, you will need to read all of the posts in that thread down to post 13.
With your existing setup, you would get improvement in colour with more overlap of images, so that you only use the centre of each image. Of course that is then slower.