I would not get a second Lookout (at least, not for actual use), and it's true that the first Lookout will become more or less dead after a few plays, but even a little bit of deck trimming goes a long way towards building a good "engine" with no +cards in the kingdom. Deck tracking and card counting also marginally help to make decisions of whether to play Lookout later in the game.
Any other Lookouts are going to be gained later on purely for the Vineyards points. I doubt this will actually happen given the prevalence of other, more useful Actions at $2 and $3 in this kingdom.
The strong Vineyards enabler in this kingdom is not just Workshop, but also FV and Bridge. If you can play 2 Bridges in a turn, you can easily pick up Actions off all 3 buys, and Potions in hand won't go to waste.