Currently, as a Roblox developer, it is currently too hard to create immersive experiences empowered by Roblox. The NavMesh is too limited and has little to no control. For instance, adding a blocking volume to the NavMesh doesn’t take into account the collision group for the current agent. Thus there’s no way to actually block a path or add a “cost” to the navmesh so that specific agents avoid a specific route. Like AI Humanoids using sidewalks and AI Vehicles using the street.
Even after implementing your own pathfinding, you would still need to implement your own navigation mesh. However, this is a bit hard IMO and just as limited as the current implementation. As there are more than a couple of variables to deal with.
If Roblox is able to address this issue, it would improve my development experience because I would be able to access the navmesh directly for manipulation or provide volume boxes that manipulate the navmesh at specific points for specific agents to allow for more variation in the different types of AI that the game allows. Furthermore, it would give emphasis to the agent parameters that the Pathfinding service already supports or extra parameters that could also be supported.
It would also be great if agent types and parameters were a bit more abstract and customizable. Currently, Roblox has released CollectionService, CollisionGroups, and Instance Attributes, it would be most convenient if the PathfindingService did not ignore the existence of these other services. By accomplishing these we would have more opportunities to be able to create more immersive AI.