Since WVM is reaching 3GB, is there a chance of releasing patch updates, rather than having the dload the entire game each update?
Since the only things that change are the scripts for the new day (tiny, even if all the scripts are in an archive) and the new images for the update.
Having a look at the file structure, it looks like you have the current version's day/previous day in its own archive file then you add them to the main archive file when the day is over.
Perhaps you could have the option just releasing the most current image/script archives? Or giving each day its own archive file, so if you have to update/refine/upscale/make betterer a previous image from an earlier day, you could just re-release that day's archive.
I'm sure I'm not explaining it very well, but I hope you get the idea.