Contagion Protocol - New AStar Mechanic

I've been working on a pathfinding system and implemented the new AStar System with a grid, pathfinder, heap, node and zombie path agent script. I think the hardest part was optimizing it properly. Initially it ran fine, however, the further the game progresses and hundreds of zombies appear, while trying to navigate obstacles had a huge impact on performance. I've finally achieved stable performance. This still needs tweaking. I.e., some zombies get stuck on corners, but I'm sure I will work this kink out as well. I'm mostly happy zombies don't run into obstacles now and try to navigate towards the player. I am trying to create this feel that the horde literally swarms through openings towards the player while preventing massive lag spikes due to the sheer amount of zombies in later game stages. I assume I'll spend another couple of early morning, maybe a week or two on the Astar and pathfinding. Then I'll continue building the first map on and off, while implementing the "Contagion Credit" system. Because why not? Earn contagion credits by beating special zombies, the final boss and successfully extracting from the map, then upgrade your characters.