I checked the code (shared.lua) and noticed the actual items it can stack hasn't changed. While I'm sure this mod will be updated over time, I'm wondering if you are planning on updating the DBL.VANILLA_ITEMS to somehow check for space age and add the extra [4] tier?

Obviously nothing that can spoil can be stacked, but outside of that there's a lot of new ore, plate, and intermediates that would fit. Since things stack nicely, it might even be cool to have a stack of stuff weigh just a little bit less than the same number of singular items to promote stacking-before-launching.