I must say that I see absolutely no difference with Tsugumi, Sora and Yuu's CG, and after a close inspection with the original one, it is a bit silly that they made a fake widescreen ratio by simply cropping the height of the CG.
That said, they definitely redesigned LeMU (be it the cg or the BG), in a good way.
As for the 3D, it is probably something similar to
White Album and
Hyperdimension game Neptune.
That said...