Not very interested in the Mathilde Rider, may have a few use in some rare edge cases, but could always get the result with other spell and loses on the primary use most of the time, better to shelve the idea for if we grab a handmaiden, that sound like it would fit them better.
What other spell can get a solid autonomous clone of Mathilde that can hit people with a sword?
This is something that would be useful as a decoy every time we're on a battle field and every time we've had to exfiltrate ourselves in a loud way. These have happened multiple times.
Scenarios where Mathilde could I use a Mathilde Rider have relatively been very common. It's very much not a rare edge case.
A handmaiden would be much, much worse at pretending to be Mathilde than a Rider:
Making the Rider look like Mathidle also does not impact its primary use at all. A Rider Mathidle would be just as good a meat shield or fighter as one that was a different shape.