How would you design a MRT system?

First of all, Merry Christmas to you, my valued readers!

I have always been interested in MRT networks. Specifically, how to design such a network. Through Simutrans, I could experiment, design and build (and even monitor and test!) my MRT network. So to start off a tour of my Simutrans transport network, I thought the best place to start would be by introducing the MRT network in my network:

An overview of my transport network, showing all the cities, but I'm sure nobody can figure out where are my MRT lines!

 Since the map above is not so clear, I specially drew a system map:

And here the MRT lines are highlighted in the overview map: (the colours follow those in the system map)

And now it's time for some history behind the development of these lines:

Initially, when I first started playing the game, I had planned for a MRT line to link up all the cities (all 8 of them at the start), but then I realized that the positions of the initial 8 cities did not allow me to simply build a "Circle line" linking all the cities. Therefore I opted to build (or "found", as in Simutrans) more cities so that I could build such a "Circle line".

Hence, the first line to be completely built was the Circle line (currently the West and East lines). This line was built in stages (just like Singapore's Circle line) :

1. The section from Heppville to Pinemouth (clockwise direction) opens. All stations except Mallilock and Malliville are operational (those 2 cities were not founded yet). Trains went from Heppville to Pinemouth, and then back to Heppville.
2. The section from Pollingwick to Heppville opens, thus Baringlock station was opened (Brentham station was not opened as Brentham was not founded yet). Trains either went in the clockwise or anticlockwise direction around the line.
3. Mallilock and Brentham stations were opened as those 2 cities were founded, thus providing residents of those 2 cities a direct and quick link to the rest of the network (and residents of other cities more places to go to!).
4. Malliville was the last station to be opened on the Circle line. This station was opened in conjunction with its inauguration as the northern terminus for the Middle line (see next paragraph).

With the opening of the Circle line, Torwick was the only city not to have direct MRT service. Thus I started to plan for another MRT line to link up Torwick to the MRT system, and with this, the Middle line was born! 3 new cities of varying sizes were founded (Newbury, Torton, and Brentmouth) so that there would be sufficient ridership on the Middle line, and initially, the Middle line terminated at Springby and Baringlock stations. However, I decided to shift the northern terminus of the Middle line to Malliville station, where there is more space to build interchanges (and space to contain people - Springby station was getting too congested!).

After a while, I noticed that the trains tend to bunch up together, even though I deployed the trains at regular intervals. Therefore, to reduce the bunching, I decided to cleave the Circle line into 2 separate lines, the East and West lines, so that the trains have a terminal station that they can terminate at (and thus I can better space out the trains). Furthermore this allowed me to add more trains to the line segment that was experiencing higher ridership more easily.

With the overview of the MRT network complete, the next few posts would elaborate on the various cities in my Simutrans world :)