Well it sounds like you'd do fine tracking the IPv6 blocks that are currently very active, without needing any significant amount of resources.
If you go the extra mile and simultaneously track /64, /56, and /48 with moderately increasing thresholds, you'll probably end up causing less collateral damage when you block someone than with IPv4.
If you go the extra mile and simultaneously track /64, /56, and /48 with moderately increasing thresholds, you'll probably end up causing less collateral damage when you block someone than with IPv4.