Scott actually has power in Vermont unlike Baker in MA because the state house is close enough that the Republicans there can uphold his vetos if decides to veto anything. I don't think Scott seems to be much of a guy that wants to veto anything though.
I imagine he will literally be quiet as a mouse through 2018 and probably skate to a quiet but larger victory in 2018. 2020 will be where the Democrats have a chance to knock him off.
I don't expect him to be "quiet as a mouse". He isn't a bombastic type, sure, but he has his own convictions and may be very stubborn if neccessary. In addition - almost all Republicans in state legislature are more conservative then he is (many - substantially), so if he REALLY decides to veto something, their support is almost guaranteed... So, no, he will not be "a king, who rules but doesn't governs.."