I like the concept of the queen. Sadly, she's almost never chosen, except with 5 players when chances of success are bigger. But then there are quite a lot of open cards.
The way we use her in live games is that she earns 4 gold when sitting next to the crown but is only used with 6+ players. It's an idea for you to consider for the online game.
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Reasoning:
- One open card is ideal. With 6 players there will be no open card unless you add a 9th char.
- Four gold is not too much. After a few rounds there will be enough cards built so that everyone gains one or two bonus gold. It's always better to take only two gold automatically (AND a special ability of the king/bishop/warlord) than to risk getting three or nothing. Usually it's nothing. Even one gold and a power is better than nothing (and going last).
- The merchant can easily gain three gold or more, and without guessing. It's not unusual to have two or three green cards built, surpassing the queen by a huge margin.
- The navigator earns 4 gold without guessing.
- Even 5 gold for the queen wouldn't be too much when playing with 7-8. Chances of success are very low.