Start with burner labs, inserters and assemblers, slow belts, and limited access to fuel. Research electricity with a new science pack and better fuel refining methods up to renewable energy.
Mods introducing new content into the game.
Transportation of the player, be it vehicles or teleporters.
Augmented or new ways of transporting materials - belts, inserters, pipes!
Furnaces, assembling machines, production chains.
Changes to power production and distribution.