Sure, but +buy/trash for +2/Fortress/farming village every turn occur to me being much stronger than a single On Gain effect of disputable helpfulness. It feels like you pay +1$ more, not for, but despite the boon. Anyway, they can't all be the greatest villages ever etc, etc.
Having played a game now, I also see the point of the mechanic. It exists to make $2 exciting. And it works! Druid in particular is a amazing card, given the right circumstances. My very first kingdom contained Fool's Gold, Courtyard and Cursed Gold, so the additional buys were very welcome. Whisp was also great here.
On a general note, I find it astonishing how Nocturne makes all kingdoms better. At the beginning, I thought ShuffleIt used curated kingdoms to show off cool combos and interactions. Having played multiple games by now, I realize that it is Nocturne as a set which is so strong that it creates exciting tricks in almost any kingdom. I complained about the power creep of Empires in the past and Nocturne is the exact opposite. It really is an enabler expansion that makes the smaller cards shine too.