@krogoth_mk2, I’m not insinuating it’s a problem with the number of trains or vehicles. My original description is just a general description about the state of the game, not anything else. I think it’s much more a problem with the population, and perhaps with the network complexity. My hypothesis is that all the people agents in the game get their job, shopping, and leisure destinations recalculated each month. But as you suggested, it might also be city-growth-related, because as I described, I made quite a large overhaul in the central city, and that grew the end-of-month delays from around 20 seconds to a total minute. Maybe I’ll let the game run for a few years on its own and remeasure after the central city growth boom drops.
But for the numbers, as asked: I have now about 50 trains, 150 trams, and 150 road vehicles. My central city has a population of 2,000, its neighbouring cities (4) population of 1,000-1,500, and the rest of the connected cities (7) 500-1,000. Totalling about 15,000 people on the map.