Furthermore this method of pathfinding as seen in the adjacent image should be easily to implement on a High-Level / Low-Level basis.
On the High level I plan for an AI to make a pathfinding check on a room by room basis to the player. When navigating through a room, I plan to have the NPC make a call to the node it reached and get the Vector3 Position of the next node for leaving the room by the desired exit (N,S,E,W).
This way I can have the NPCs only make a room path check every time the player changes rooms, and the NPCs also only path through the room they are in, and through transitions.
There is certainly room for optimization research, but not only is this a University Project I also believe in getting a system to work first, and then optimize the code.
The plan for AI right now is to write the various scripts and methods to have the network of nodes connect on runtime; as when a model is loaded from the pre-fabs in Unity, the public settings are saved, so being able to move from one node to another can be saved as a node object reference on each (and as is my plan) but for saving I will need to abstractly save the positions and rotations of the rooms, so I cannot save the connections between rooms.
The idea for this is on loading a map, each room's portal node (shown as a green sphere) will make a call to its adjacent room to get the position (if one exists) of the neighboring portal node, if none exists then the node becomes a non-portal node and can only be used for room navigation.