As you do not have a help thread for Extended - I will ask my question here.
I have not played for some time (and even then by not much).
So I downloaded a recent update. (about 3 weeks ago).
Starting in 1750, I connected all Industries.
Then used Hackney carriages for passengers.
My first Town I put a bus stop about every 10 tiles. (20 stops) but I got no passengers.
My next (a City - twice the size) I put a bus stop about every 20 tiles. (10 stops) and lots of passengers.
So what is the recommended distance for bus stops in 1750.
Also does this change (up or down) as the game progresses.
There is no standardised ideal distance, as it will depend very much on the circumstances. However, you will benefit from bearing in mind the following:
(1) passengers will walk to their destination if they can get there more quickly than by public transport (taking into account waiting times as well as travelling times);
(2) passengers walk in a straight line from origin to destination at 4km/h; and
(3) passengers will only use transport if it takes them to where they already want to go, and bigger destinations are more popular than smaller destinations.