I finished chapter 4:
Spoiler:I liked it, but I think I liked the first 2 chapters better.
I am glad that Grace and Gerde stopped fighting; I was not surprised at all that Gerde loved Gabriel's uncle (this was hinted at in GK 1).
Ludwig's history was intresting, and his castle you visited were beautiful (makes me think even more now that they filmed the Ritter's castle inside some old victorian mansion in the US).
Again not a difficult chapter, Grace's chapters feel more like early Gk1, more investigation rather than puzzles.