There is noticeable server lag and a persistent log warning for an incorrectly configured config file that never gets resolved.

The error might be from the value passed to DefendVillageGoalGolemMixin from the config option:
""How low of a reputation of a player should have to be instantly aggroed upon by guards and golems?" = -100"

latest.log

Can you please submit a report using the spark mod while recreating the server lag? Would be especially helpful with diagnosis.