
(Assuming programmer no longer has plans to code the following, that he thought of...)
Maybe instead of including all mods in a larger and larger package, you could make your program download the mods from one of at least two available mirrors.
One mirror is already available: http://www.popot.org/custom_levels/soft ... umber>.zip (where <number> is a 7 digit mod number; add leading zeros)
If you would mirror all these files somewhere else, your Total Pack would have two mirrors the user could pick from to download any mod the user wants to play.
I'm not sure if that would work with all the functionality in the Total Pack though, it's just a thought.