5 additional tiers of belts, splitters and undergrounds. Custom belt speed for all 8 tiers in items/second.
Mods introducing new content into the game.
Augmented or new ways of transporting materials - belts, inserters, pipes!
Can you add loaders for each of the belt tiers? (either in a separate mod or added to this one)
Until Mod author does add loaders, Comfortable Loaders with the more belts addon works, and uses custom speeds.
https://mods.factorio.com/mod/more-belts-loaders I have released an early version of a loader mod I have been working on (don't really have the time to do much recently). This works with the current tiers of belts and their speeds.