Is the issue that you're running out of memory or just performance? If it's memory then what about just connecting a single set of animCurve nodes to all the skeletons/rigs? (you'd obviously want to script the process of connecting the existing curve nodes to the new skeleton)
Hmm yea with 200 odd characters walking around I'd be suprised if it didn't slow down a lot tbh. It's going to use up a lot of CPU/GPU time just to do the scene update with that much stuff going on because every time you alter the current time every node downstream of an animCurve in the DG needs to be calculated again. I…