I'm loving the new maid characters introduced. They really added more life to the story, simple as it may be.
Technically, they aren't new. Just very under-utilized.
Head maid first appeared in Chapter 12.
Chapter 13 included both maids with nearly the exact same information blurbs about them as in Chapter 27.
I don't believe either one appeared after that until Chapter 27, which is a shame because, as you said, they are fantastic additions to the story (especially providing a key connection to her grandfather's approval of their relationship).