I'm writing a little plotting library for LCDs. I'll try to publish it once it's more polished. What do you think?
For now it supports reading data from a Vector, arbitrary scaling on both axes, linear interpolation, different point styles (square, circle), arbitrary many graphs.
I'm not sure if it would be helpful for your project, but you might be interested in the concept of the grammar of graphics (https://towardsdatascience.com/a-comprehensive-guide-to-the-grammar-of-graphics-for-effective-visualization-of-multi-dimensional-1f92b4ed4149).
I use a version of this in R as implemented in ggplot2. What is nice about it is that you can use standard text descriptions to build an arbitrary graph.
It's a pretty interesting concept. I don't want it here though. I'm just building this for my own needs (mostly fun).
I'll look into this as a consumer though next time I need to plot stuff on a desktop :)