This is an excellent idea, unfortunately bots aren't that smart knowing where to go unless you implement premade pathfinding maps for each map you have. I did have this idea but it would take forever for torkscript to calculate which way is the best (remember having to link everything, so if I did this manually it would take much longer)
Maybe if I created a pathfinding dll or use an external DLL like lua/java this actually will speed up the process much faster.
I actually did this in Slayer - when you started a minigame, it generated a navigation mesh of everywhere that bots could go. Unfortunately, it took 10-20 minutes to generate on large builds, so I scrapped it.
I currently have a prototype of a much faster, more efficient system, but it's buggy still. Once the navigation mesh works, it will be tied into the team-filling bots that Slayer already has.