Okay so there is a game I came up with in about 2001 which I never made and I once again find myself pondering about a fundermental part of the game with which I'm not sure about (This is using the orignal Games Factory which I don't think restricts me too much but just so you know).
I wanted to make a serial killer based on a serial killer storyline I saw on a realy bad early 90s Aussie soap. In this game you play the serial killer himself and the onject of the game is to kill as many people as you can.
In my mind, it's a top down game where you can explore a large town. There is also off the beaten tracks and a forrest. The idea is that you attack (various attacks and weapons) a wandering innocent and kill them without anyone seeing you do it. Then you have to get them into the boot of a car and drive to the forrest and bury them. The object is to successfully kill and bury as many people as you can before being found and arrested.
If anyone of the other people should see you (invisable line of sights - like in the PC game Commandos 2? Anyone remember that?) then they begin to walk to the police station to inform the police. To avoid them telling the police you have to kill them too before they reach the station. if they reach the station then many police will begin to hunt you down. Of course, you have to be careful that people don't have you in their line of sights when you commit thse further murders. because the whole situation would snowball! You can only fit on body in your car at a time. Maybe more in a jeep.
Quite Dark eh?
Anyhow, I am not sure how you would get the physics of this game working well as people going towards the police station need to aviod constantly just hitting the walls of various buildings. and the police would need to come from the station and towards your character while sticking to suitible routes. What I certainly would not like to see is people looking like they were flipping out and walking against walls.
What you've said is really quite broad, but in relation to the route question, there's a lot of different ways to go about it. Why not start working on it and ask when you are presented with a problem instead of hypothetically? I'm not sure if there's TGF extensions for pathfinding, whether it's MMF only or not I'm not sure.
In any case, I don't see why it's not possible to do in TGF. I think your only restriction will be playing field size and object limits. (Which is where MMF would likely triumph over TGF in a situation where you want a large town and forests)