Now I'll admit that this last one might be a little wacko but after reading some of the "serious" or was it perhaps the most common suggestions I'm not so sure.
How about them pipelines! I mean is it really that common to ship oil from an oilrig to shoore. It should be possible to build them on ground, under ground and under water, that might be difficult.
This one is not possible and I dont think it adds much to gameplay, ofcourse I am not the one to decide tho.
JFK YOU ARE A GENUIS!!!
How about this guys, a lot and I mean a LOT of liquid goods are transported by pipeline, yeah? To implement this we could:
1. Have pipes that are specifically designed to carry one type of liquid. Pipes that get old after a while or rust or whatever after time and upkeep costs result.
2. New pipes like steel or even platium pipes that are designed to carry one type of liquid faster (like new trains).
3. Bigger/Wider pipes to carry more at once. (Like a longer train.
4. PUMP STATIONS (Pump stations, which act as the engine for a train) which need to be placed at certain intervals to move the liquid along.
5. New pump stations with more efficiency (less breakdowns) and more power to move the liquid faster. They can be placed like stations in order to handle more pipelines at once.
6. Different liquids (ok we can still have water and oil) like the oil refinery or a sub-industry after the oil refinery that is a central heating plant that can be used to heat the oil and supply it to towns (people that live in european countries will understand what I mean) and we can have that in maybe the artic map.
o - Another liquid could be maple syrup or cola for the candyland map.
o - Gas pipelines like you mentioned.
7. Payment would be based on a "amount delivered" per day.
8. Although this kinda kills the whole logic aspect of the placing of signals and rail network design
This could be a lot of hardwork, and it is something i cannot clearly do. I can draw grfs, nor make code for them or even program new code into the releases to handle this new transportation/payment technique.
Pipelines can be built linking oil wells to refineries,etc. but three's a need for realism in how they compete with tanker trucks/trains.And a matter of bureaucratic clearance.(How about local authorities not wanting hazmats through certain zones?...also an interference in routing uranium fuel to and waste casks from nuclear power plants,if added.