Did you read my suggestion about using unhappiness to slow down work speed, if you repeat something it increases your unhappiness (exponentially?), especially on unessential tasks (like making buckets). That way when you're making your nth bucket you'll be really slow because you're so bored. As farming is repetitive by nature it should have a low exponent and a low unhappiness, which is decreased further with the nature slider. The only way I can see to code this though would require storing the time you last performed each action, which might make it infeasible.
I do not have an issue with no lifers, despite my opening statements, I just think its silly that the way to get ahead is to find a task that gets lots of LP and repeat it, I would've thought the game should reward people who build up their village, group, homestead, linearly, as in farm a bit, build a bit, craft a bit, fish a bit, hunt a bit, repeat.