Hi Rulrus,
Also interesting to know - you can change the brightness / darkness of the Impostor Materials in the MI settings. Also try adjusting roughness and specularity to fit your model!
What else we did was to let Impostor Baker render out “Opacity” instead of “Depth” map for a very hard / clear additional opacity map that we combined with the soft one in the basecolor alpha channel. Eventually, our billboards looked much more solid and true to the original’s color.
Best regards!