Doh! Good point on the telescope being a 18xxx mod. I spaced out on that one.
Hrmmm ... so your lady basically wants the smallest possible pv with exchangeable batteries.
I will say though, 14500 battery devices do tend to underperform. Now that might not matter to her as long as shes getting a good vaping experience. And of course, 14500 batteries have a significant lower capacity so indeed, she will be replacing them more often.
The smallest digital that comes to my mind atm is a L-Rider Robust. Comes in girly colors too.
Otherwise I like the baby bullet recommendation for mechanical.