Have you thought about paying a technical genius to utilize the huffman encoding of the map storage better, causing your map to physically be smaller in size?
Many years ago I made a custom race mod on Warcraft 3 with 6 custom races, and a model file for almost every unit of almost every custom race.
Based on my original projections, I was able to reconstruct the entire Warcraft III game in a new format that was still playable where the entire game itself was 100 MB, and my mod on top of it was about 60 MB more, so then in 160 MB people could download the entire game, and the custom races, etc.
Most likely, having your map be so large is the result of bad technology. I do not know this for certain; perhaps your custom Reforged models include fine tune visual details that actually require 250 MB of storage. But I think this is very, very unlikely.
Reforged itself is guilty of extreme redundancy. If you take most Reforged models and trim away the redundancy, their size would reduce probably in half or probably much less. For the 30 GB download, Activision just literally doesn't care. The best solution for them is the one that is quickest and simplest in the office.
But if you're fighting a 250 MB limit, it's possible that the same parameters do not apply. It might be more advantageous to use the 20 years of modding knowledge at Hive to create 3D files that visually look the same, but load into the huffman encoding and end up much smaller.
I guess if you filled your map with custom WAV files, that might be a lot harder to compress, though. It depends. But I'm just curious
