As Scout is often being mentioned as the worst card, I thought, increasing it's strength wouldn't even change a lot. But I think, I'm wrong.
Let's just imagine Scout was a cantrip, that said: "reveal the top 3 cards and draw any green ones of those revealed cards". Without trashing, this could be nice to green early. Something weaker than Cartographer and Laboratory, which are both reasonably well $5 cards.
So maybe adding another little benefit instead of a "certein draw" would fit better. Something like +1 coin. Even then, I think, Scout would be worth it.
Adding a +buy always is a way for a card to shine, whenever there is no other +buy availible.
Adding +1 action would make it some Anti-Farming village, but still as great for engines, I guess. (You leave just those cards on top, you would like to draw to get your engine running. So you only need a drawing card on your hand together with Scout.)
Maybe this is, why Scout ended up, like it did. With all the new alternative VP cards, Scout would fit much better at $3, so that you could buy one, if you missed silk road or feodom. It also could help enable conspirators, but again, they cost $4, so there's kind of a conflict.