Quote - I have the non-commercial version of Atangeo Balancer ( $26) . It works very well for me. The picture is a V4 reduced to 10% of the original vertices count. The texture mapping is retained and the groups are maintained and welded. Pointing a copy of the original V4 Cr2 at the new mesh gives a good low resolution useable figure. The swimsuit and hair in this picture are unmodified. Note that Balancer has maintained the volume of the figure so the swimsuit still fits as good as ever.
A downside to reducing the mesh vertices of a figure is that morphs won't work. The latest version of Balancer has a feature which can maintain the verticies at a boundary, so I think it would be possible, for instance, to make a low resolution body which can weld to the original head. That would allow the original head morphs to work. I haven't tried that myself as yet.
I have no connection to Atangeo other than as a satisfied customer

NICE... have you tried animating any of the models you've reduced? I'm really curious about that aspect.
Does it keep the rigging etc... for adding BVH files to the "shrunken" model.