It turns out there are dozens of possible ways to arrange the notes into a pentatonic scale. A pentatonic scale is any scale that has five unique notes per octave, a simplification over the standard seven note major scale. The pentatonic scales tend to sound raw, earthy, primitive. About 40% of the kalimbas Hugh Tracey encountered in his travels around Africa had various sorts of pentatonic scales, and Maurice White of the band Earth, Wind and Fire put his kalimba into a pentatonic scale to make it resonate more with Africa.
My take: With fewer notes, there is less potential for making mistakes on the pentatonic scale. This frees one up to play more powerfully and more emotionally.
It is pretty easy to change the tuning from one sort of pentatonic scale to another - this is something you can do yourself. You could explore all of these exotic tuning destinations on your own, with a single pentatonic kalimba.
As it happens I have transcribed onto tablature a couple of songs that I improvised on the pentatonic kalimba, each in an exotic tuning. I happen to like them both a lot! The tablature makes it very easy for you to learn them and both are available right here on this page. In addition to the tablature, the songs are also presented on video, giving you some great tools to help you learn how to play like a pro!