Thanks for all your answers.
All of the hardtails suggested look to be a bit overbuilt for mrsbunks “wheels on the ground” style. Also, the 14″ mens frames (Bfe, Santa Cruz, On One) have quite similar measurements and geometry to her current frame, so she probably wouldn’t get much benefit from the change (though this is secondary to my need to fettle).
I think I’ll keep an eye out for a demo tiny full suss for her to try out, as there looks to be a few decent choices. Can’t imagine there are many demo bikes built up in her size though.
I still think there is a gap in the market for good quality not too hardcore light and agile hardtail in tiny size. Not in Orange though, cos then it would look the same as mine. Just, y’know, putting it out there…(*COUGH* Cy, *COUGH* Brant!)
Meanwhile, I’m going to spend the next few hours browsing through mamadirts impressive bike history!