When duke shines, it really shines. But it's almost unusable in 15% of games, and can be easily beat in maybe 10% of games with good engines? A card that is beat in a quarter of games is not the number 18 $5 card, which has alot of elite cards.
I guess the bottom line here is, which "elite $5 cards" are getting the short shrift here? The next 6 cards in line are (from #19 - #24): Festival, Highway, Bazaar, Jester, Upgrade, and Merchant Ship. It's not like any of those cards aren't completely ignorable/useless on a significant percentage of boards too -- and the boards they ARE useful on, they're basically never ever a MUST buy.
I definitely disagree with this:
* If you have good reason to go engine and Bazaar/Festival is the only Village (or Festival is the only +Buy) then they're must-buys for sure.
* Highway is very often a dead card but sometimes the key to incredibly strong combos, so it can be a must-buy. It's overrated though.
* Jester is not the best of attacks, but virtually all attacks have situations where you ignore them at your peril.
* Okay, perhaps Upgrade is rarely a must-buy. But it is so, so frequently useful.
* Yeah, Merchant Ship is useless on a significant % of boards, and even when it's good it doesn't really ever warp the game; I'd put Duke above it. But that's because Merchant Ship is about ten slots too high to begin with.
If you go lower, I'd say that (even assuming Duke is better than I, perhaps unfairly, think it isn't) City is definitely a card which is buyable more often than Duke, and just as game-changing when it's good. City was underrated pretty badly here, to be fair.