They would obviously affect the reach/range of certain items and thereby increase the area covered. Possible items include:
- Roboports (There could be module slots inside them too, SM boost charging speed, EM reduce energy consumption, RM to increase range) (Similar to: viewtopic.php?p=98440 )
- Radars (There could be module slots inside them too, SM boost scanning speed, EM reduce energy consumption, RM to increase range) (Similar to: viewtopic.php?p=88542 )
- Electric Miners (SMs & EMs obviously, RM to increase range)
- Gun Turrets (When putting modules inside them they start to require energy, SM boost shooting speed, RM to increase range)
- Laser Turrets (SM boost shooting speed, RM to increase range, optionally EMs decrease energy consumption)
- Substations (RM to increase range)
- Beacons (RMs: There would have to be 3 slots in Beacons to make it an interesting choice if you want to extend the range or push speed/efficiency, with 2 slots it would be too limiting)
- Advantage: Increases area covered by the Item.
- Disadvantage: Increases the energy consumption of the Item it is placed in considerably (but not enough to justify placing an additional item)
If EMs would be applied to Turrets then the EM module will make a huge difference... that's when Turrets would have to be balanced A LOT better. That or just don't allow EMs inside Laser Turrets.
The most obvious problem would be "why use range modules when placing an another item is so much easier?" but that is basically the same argument when using Speed Modules. And somehow I don't know how to argue about that mostly because it is a matter of taste if you want a more compact factory at the expense of additional energy consumption.
I would at least like to discuss the possibility and see what other people here on the forum think about it. Maybe someone has an idea on how to alleviate the problem that placing additional instances of the same item is more worthwhile in most cases.