I just saw this poll and the thread.
My vote is "yes". I have played several games starting with passengers transport. Usually it is easier to start transporting something to an industry, but you can start with passengers. When you are not used to how it works it seems almost impossible.
But once you find out it works fine.
Two towns are actually enough for a start. Should be a fairly long distance from each other but NOT longer than you can afford to build a train line with a station in each city, buy a train and buy busses and bus stations.
So make a train station in two towns. In each town connect bus lines to the station and connect the two stations with a train.
The train line makes the money because of the distance. The bus lines supply the passengers for the train line so it can make money.
Make sure that the cities have a size so you can make several bus lines.
Hajo's suggestion with 3 cities is probably easier by the way.
An extra thing: You can help the cities grow by adding roads.
If you want to make it easier starting a game with passangers, then change the start year to a later year than the default year 1930. In the Simutrans game folder find the folder called "config", open that folder and find the file called "simuconf.tab". First make a copy of that file and save it somewhere else so you have a copy of the original settings. Then open "simuconf.tab" with Wordpad. Find this part:
# Starting year of the game:
# Setting it below 1930 is not recommended!
# You will have problems with missing vehicles, do not complain if you do so!
# Setting it above 2050 will render game bit boring - no new vehicles.
starting_year = 1930
Now instead of having
starting_year = 1930 try out another year.
starting_year = 1980 I found is a good choise then you will have faster and bigger busses and faster trains. For the trains start with just one or two platforms at the stations, you can later on make them bigger.
Once you have got more experience you can take the challenge it is to start at the year 1930.
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Whether you start a game with passengers or industry service there will probably be a point where you are almost out of money. At that point you need to let the game run just making money untill you have enough money to expand.