Wow. I have some substantial deviations from this list, now.
Quarry: I have this in my top 10. Without +buy, Quarry is a Gold for most of the game. Opening with a Gold is pretty good, it turns out. But Quarry really shines when paired with a cheap source of +buy. With two Quarries in play, you can use (almost) all of your buys on 5-cost actions. Combine Quarry with Haggler, Talisman, or Border Village purchases for insane results. Sure, Quarry is a bad card once you want to start greening. But it's a great target for most Estate trashers (Remodel, Salvager, Bishop, Transmogrify, Remake, etc...). Convert that Quarry into a Duchy, Gold, or engine piece, depending on your need.
Remodel > Salvager: I see these cards as serving similar purposes: Estate trashing, removing undesired cards, and generating victory points.
Estate Trashing: Remodel is better when there are multiple good engine pieces that cost 3 or 4 coins. Salvager is better when it's important to reach 5 coins.
Removing Undesired Cards (fast trashers, junkers after junk is gone, gained Silvers, Rats, etc...): In the mid-game, with Remodel one is likely to be able to get two 5-6 cost cards after trashing one of these undesired cards. The advantage of Salvager is flexibility. If you want a power 7-cost card, you can get that. If you get an unusually strong or weak hand, you can adapt to that and make the best of your coins with an additional buy. Remodel bonus: gaining 2-cost engine pieces while trashing Curses, Ruins, or Copper.
Generating Victory Points: Remodeling Gold into Province is well known and powerful. If you expect to have Golds or 6-cost cards, Remodel is great for grabbing extra Provinces in the endgame. Salvager cannot generate as many victory points as Remodel in the best case scenario, but it can help generate 8-coin hands by trashing another action card (whereas with Remodel, you may have to settle for two Duchies or worse).
Which is better depends on the board and one's strategy, but I tend to prefer Remodel.
Fortress > Plaza: Both are villages; let's examine the additional benefit. Many boards contain a decent trash-for-benefit card that you want to use for Estate trashing (like the above-mentioned cards). There is a period of time between Estate trashing and victory card gaining where these cards are looking for something worthwhile to do. Enter Fortress: the village that always provides a good target for trash-for-benefit. A really good target. There are other trash-for-benefit cards that work well with Fortress (Procession, Apprentice, Stonemason). Fortress is a good counter to trashing attacks. Fortress is also good to have with cards where trashing might be undesirable (Mercenary, Trade Route, Rats). Fortress can also be unusually put in hand mid-turn by cards like Watchtower (with gainer), Hermit, Doctor, and Lookout. Plaza, on the other hand, almost always provides a small benefit (coin smoothing) - the exception is in the presence of fast trashers. This is a decent benefit, but nothing special. Plaza is only great in conjunction with draw-to-X cards (and Menagerie). Unfortunately, there are only four such cards - compared to dozens of cards that work well with Fortress.
Advisor > Caravan: Both provide a nonterminal two cards. Advisor provides the worst 2/3 cards immediately. Caravan provides two average-quality cards - one this turn and one the next. Advisor provides a little faster cycling, at the downside of being unable to play one's key card(s) as often. But Caravan itself misses more shuffles than Advisor. The deciding factor for me, though, is that Advisor gets better as one approaches being able to draw one's whole deck; Caravan gets worse. If I'm playing with Advisor or Caravan, I generally expect to reach that point - and sooner rather than later.