How much of a scale difference is there between a soprano and a sopranino? (I googled but really didn't find anything definitive.)
There was a time when 664mm was considered standard scale for classical guitar (the Segovia era, if you will). Then 650mm came into vogue (.55" shorter than 664mm). Now people are clamoring for 640mm like it's some kind of magic bullet that will make it easier to play (.39" shorter than 650mm). That's not even half an inch over the entire VSL (vibrating string length). My 664mm seems just as easy to play as my 650mm, but it's a flamenco with nice low action, which probably helps.
Small hands don't seem to be holding either of these little girls back playing what look like full-size guitars to me.
http://www.youtube.com/watch?v=njG_dQC-cnk
http://www.youtube.com/watch?v=LaHaRUPfKok
I'm just curious as to how much of a benefit in ease of playing the OP would actually get with a sopranino vs. a soprano. Sig says she has a Mahalo, which is on the lower end, so I'm wondering if perhaps the action is too high, making it harder to play.