Creating a point cloud engine using shaders/meshes

I want to create a simple point cloud engine that takes in a text file of the format: x,y,z,data (for example 10.1, 0, 0, 12.5) where the "data" is a field that determines color based on bin. So if the data is between 0 and 10, the point is rendered as one color, and a different color for 10-20,20-30,etc.

I have no problem reading in the text file and storing it into a relevant data structure. I want to take each point in the text file and for each point that is the same color, store it in a mesh. Then simply display the mesh of colored particles.

The hard part is I expect to have millions of particles for the data I'm given. Since meshes max out around 65,000 vertices, I will need to make multiple meshes, hence why I want to group the meshes by color.

I understand how to add the vertices and colors to a mesh, but I believe I need an efficient shader. The shader only needs to take a vertice and apply the color (more transparent as the data value gets lower). I've watched some videos and read docs on shaders but I want to get some expert input on designing this efficiently for the hololens