Some notes from the guy who made the linked expansion:
1. I tried to make the benefits mostly "draw a card", because I was worried about memory problems, especially in multiplayer. Drawing a card is immediate: getting actions and buys requires you to remember when it gets to your turn. This might not be as big a problem as I think, but it's worth remembering.
I was thinking that them being Duration cards would help solve this. As well as push the idea that "yes, you actually need to look at what your opponent is doing on their turn." At the start of your turn, it should easily jog your memory by just looking in front of your opponent's and seeing what Duration cards they have in front of them. Although it still could get tricky in 4-player games, with all those little +1s out.
2. Cards that help everybody speed up the game a lot. It also makes +Buy a lot stronger. +Buy is useful in the original game, but only when the game gets to the point point where you have excess money. When you help everyone, you reach that point faster.
Good point. I was thinking it'd make it more like Prosperity games, but that only holds when there are the big VP options to go along with the engine. I was thinking stuff like this:
Empire (or "Orchard," to go with Garden/Vineyards theme)
$7
Victory
Worth 2 VP for every 10 cards in your deck (rounded down)
Super Garden...although it's a lot harder to make work with a "Copper flood" sort of engine, and also out of reach of Workshop/Ironworks.
I will also need a Goons/Bishop type card, or more than one. VP tokens will be featured in this set.
3. The usefulness of the effect given to the opponent is directly related to how well they can use it. There's little difference between an 8 card and 10 card hand if there isn't +Buy, and there's not much point in getting +1 Action unless you have plenty of actions. So, you want to make sure that there is generally a use for the benefit they get. Cottage is an example of a way to do this: it probably won't be picked up unless there's an engine, so the extra action is going to help.
Yeah, I wanted to make part of the skill in this set adjusting your own deck to what your opponent buys. Like, if they're getting lots of Cottages or Pinkie Pies, to go more Terminal heavy than you normally would.
To make the strategies more dynamic, and not just a self-reinforcing loop of "everyone ends up doing the same thing," I should also add cards that give opponents benefits contrary to what the card does for its player. Like an exaggerated Embassy...it wants high variability in your own cards (Golds to keep, Coppers/Green to discard), but gives your opponent middling consistency (Silvers).
Coincidentally, with cards like my Princess Celestia I thought it'd be cute for them to be used as a semi-attack in some situations. Like, if you're opponent is going very Treasure-heavy, and it's likely to be a dead card. That's why it's specifically not a "may gain.
Cottage
$2
Action - Duration
+2 Actions, +1 Card. While ~ is in play, at the beginning of your opponents' turns, they get +1 Action.
Assuming ~ means "this card", this card (as written) acts identically to Village. Assuming this isn't the intended effect, you may want to give it a next-turn effect.
Yup...
Cottage
$2
Action - Duration
+2 Actions, +1 Card.
At the start of each other player's turn until your next, they get +1 Action.
And accidentally Procession'ing Horse Traders to throw away all my last key engine cards in hand...)
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