I know its been a while since this post, but I just wanted to come on here and say a huge thank you! Setting fExtraTaskletBudgetMS=1.6 in my skyrim.ini fixed this issue instantly! My settings that work like a charm (I have a ton of mods)
[Papyrus]
fUpdateBudgetMS=800
fExtraTaskletBudgetMS=1.6
fPostLoadUpdateTimeMS=2000.0
iMinMemoryPageSize=1024
iMaxMemoryPageSize=3072
iMaxAllocatedMemoryBytes=2457600
bEnableLogging=0
bEnableTrace=0
bLoadDebugInformation=0
Thank you again!