This submod slows unit replenishment rates to take 1.6x longer than the default mod. Where most units in the mod take either 25 turns (6.25 years) or 33 turns (8.25 years) to become available again after recruitment, they now take 40 turns (10 years) and 52 turns (13 years). There are a number of units that have different default rates than those two, and I combed through the edb to try and make sure I caught them all and adjusted accordingly. Some units already had rates of 100 turns or more, those I did not change as they're mostly client rulers or other specialized situations.
The idea is to make units and armies more precious, battles and wars more decisive. Maybe even lessen or prevent stack spam for super factions in the long run (to the extent that it might still exist in the mod at all). I ran a simmed AI campaign for 425 turns, and it seems to be working as intended. The largest factions had around 10 big stacks, most others around 5 or so. And the change didn't seem to negatively affect faction expansions, except for Rome which was the initially player-controlled faction in the hotseat campaign set to AI control. My assumption is it doesn't get all the bonuses that other AI factions get or something because hotseat campaign seem to always turn out poorly for the first-selected faction.
Spoiler for map of 166 BC:
Below are the changes made to the edb for reference. Hopefully I haven't missed any, but if anyone happens to try this and notices refresh rates that seem too quick or anything else out of place, please let me know.
Spoiler for changes/notes:
Installation: first make a backup copy of your default export_descr_buildings.txt (...\Medieval II Total War\mods\ebii\data), then unzip the submod file in there and overwrite the original.