Just notice that module with productivity are not limited in default. Maybe a option to add these restriction back can balance them better? Just feel this feature quite too op.

Bob use this line to add limit:
limitation_message_key = "production-module-usable-only-on-intermediates"

Wait, i got an mistake, this is just a message...

Should be these lines:
for i, module in pairs(data.raw.module) do
if module.effect.productivity then
module.limitation = productivitymodulelimitation()
if not module.limitation_message_key then
module.limitation_message_key = "production-module-usable-only-on-intermediates"
end
end
end

you want me to limit the ability to use the productivity module on everything except raw materials?

Yeah, like other productivity modules did

Okay. will try