I'm just so so so used to playing with money and the more park staff you have the less profit you make, so just about all of my coasters had a path intersection where mechanics could service the coaster from the current cell yet peeps were prevented from going back. After quite some time, I abandoned the 'conserve on park staff' method, but nevertheless still had these 'service' paths.I tried to keep (at least this one ) "simpler" : all paths that exit a coaster, are "exclusive" for the leavers of that coaster and have no connection with any other path whatsoever, untill they arrive in the next cell. So if you see anyone on that path going in the other direction, there must be something wrong. Rather clear.

I noticed that peeps behaved (followed the yellow brick road) as long as there were no intersections or shops. If a peep came to a shop, it might turn around and go back to the coaster. A few instances, I added 'no entry' signs by these shops to keep them moving along in the right direction.Of course at some points, even the leavers of the coaster want to turn around and return to the coaster they just left. Well, than they can only come at the exit again and have to turn around again as they cannot enter the exit. Still, to keep them in the one-way direction and make sure no one is walking into the wrong direction on these paths, I placed no-entry signs at the points they where liked to turn around, but in fact these signs are not really necessary.

So nice, all those different solutions!
At one point I noticed that more peeps were riding the coaster in my second cell than my first. That is, from opening my park to say around year 5 or so, the total number of peeps that had ridden coaster 2 was greater than coaster 1. I was like, what is going on here? Then I checked my 'special' flat ride in cell 3 that had the exit which lead back to cell 2. It had a 'high' popularity and had a lot of guests riding it.
The exit path had three choices (not counting backwards) for which peeps could walk, one of which lead to another two chioce ('T') intersection, and one of these paths lead to yet another 'T' at which if the peep went right, he/she went back to cell 2. Now if these peeps' decisions were random, then probability theory would state that a peep had 1 in 12 chance of making it back to cell 2 (1/3 * 1/2 * 1/2).
So I watched in amazement as groups of peeps would exit the ride and like greater than 9 out of 10 would go right back to cell 2. I figured that I would trick them by making a ride that they wouldn't like and it worked, but then I said, well, most of them want to ride cell 2's coaster over again, so if I make them happy, and give them a ride they like, then maybe they'll come back and ride cell 3's coaster.
I never did go back and experiment with this. Hard to believe that they had that much AI.

You're right so many solutions.
