Oh, I just checked back and noticed that you improved the game. :D Fixing the jitter (mostly, the text in the upper bar can jitter a bit, but it's way less of a problem)

The throughput of the nodes is now at ~1.1k Items/s, which is quiet an improvement. Good job! :D I am not sure how you are doing it right now, but I think I would let them calculate the possible throughput and then just animating... 20 Items/sec? 30? Whatever looks nice. So I would try that they would need the least amount of updates/calculations per second. Maybe create a switch that calculates everything like normal, if it's below 20-30 Items/second/Node and if it is more work with calculated values/amounts of items. That would reduce the ticks down to 1 calculation/node/tickrate.

Of course you would have to handle the amount of items correctly if there is a bottleneck of large packages, for example, and you would have to create a most likely spread of packages when the player pauses the game. Or maybe you just let the packages vanish in the nodes...

Or you change the value per package, so that one package is now worth 20, for example, so that the system has to tick a 20th of the original packages. That would make the work of displaying the actual packages in the node easier. ^^