Our team has discussed pneumatic versus electric actuators before and that was the original idea for the project. My personal worry with pneumatics is that until the number of actuators is increased to something like a 60x60 table, the cost of getting everything started might be higher, whereas with electric actuators, the scaling itself would become expensive. But maybe it is time to revisit some of those ideas again. And I definitely see the point now of the unneeded touch sensitivity of motor faders.
Thank you all for the advice that you have. Really is helping me think through this project. There is not a deadline for the project, and is something that I enjoy working on in my spare time. Brings together a lot of fields that I haven't worked with in the past (GIS, programming, Arduino, design, etc). Definitely learning a lot!