Big MacOS Install PKG Versus Downloads

Question

I am creating software in MacOS that has over 10GB of assets associated with it. I can create a pkg that properly installs these but I have two problems. First, the notorization process required for Catalina is going into introduce a brutal bottleneck and weeks of debugging. Second, the distribution of this file is quite cumbersome.

I am looking at creating a minimal installer for the primary code components, but then downloading the thousands of assets during install. Is there a standard way to use a pkg to do this or do I need to roll my own? What is the standard way to do this?