I found myself wondering how effective a very basic engine could be, i.e. one that uses only three different cards. Since engines usually require 4 things, namely trashing, villages, draw and payload, there need to be cards that can do several of these things. Cards such as Steward.
On a very basic version it would only desire any village to be an engine on it's own. Yet, this would be a very bad engine since it needs to gain at leats 10 cards before greening and it can't green very well. It also needs 5 turns of trashing your 10 starting cards, so you could maybe hope to be ready around turn 11 or 12 to pick up one Province per turn. Too late for many other strategies. You could, of course, add attack cards to slow down your opponent. However, I wondered if some simple gaining like workshop would be enough to catch up.
It's pretty obvious that every card potentially strengthens this engine, but I wonder wether the bsic version consisting only of Steward, Village and Workshop would be good enough to compete against Big Money strategies. Maybe you need to exchange village and replace it by farming village (you don't want to draw green cards once you start greening).
Is there any estimation of what can be worth it or how much it takes to be worth going for the engine - especially without +buy?