This is really interesting, I'm making something similar as a gift for my wife ( I didn't know this product existed). It's much smaller but shows a map of planes and their live location in the air space near our home.

I have to say though, it's very weird you're hitting API rate limits. airplanes.live is a free no-authentication needed API that lets you poll it 1 time per second, and with each poll it returns flight information for ALL flights in up to (I think) a 250nm radius.

I doubt this commercial product could use that API but my point is that this data isn't that valuable. Additionally for the size of the thing the could just put and adsb receiver in it....