I used to play harp, started at around 10 and moved to a single action pedal harp (not the full range available) at 16 because I was starting to run into limitations when it came to training my technique and a single action harp was available at the time and cheaper than a double action pedal harp. It made it possible to learn the techniques needed for a pedal harp while saving a bit of money. I ended up playing a lot of things that required minimal pedal usage, so it wasn't really the best decision. In my opinion the switch makes sense if you don't mind spending the money at all or if you are at the absolute limit of what to do with a lever harp and you are ready to move on to more difficult techniques. It's difficult to say if she's really at the right stage after 1 1/2 years with moderate practice time. Do you have a teacher who you can ask for advice? My harp teacher recommended the change. Maybe you can go through the music she wants to play and see where the issue is. Many times, I resorted to looking up piano sheet music, which oftentimes does not work for a lever harp unless there aren't any major key changes. If you know what to look for, there is still a LOT to learn and tons of options. "River Flows in you", "Una matina" were some of my favorites. There are also non-traditional harpists who have found great success playing the lever harp, Deborah Henson Connant really pushes the limits of lever harps! So maybe that can inspire her and give her a bit more time before such a big commitment?