I kind of agree. On the other hand, I can sympathize with the idea of bumping the price up, even without adding special abilities. It's one of those cards where the power is determined by the cost, rather than the cost being determined by the power. Farmland is another good example: It's probably not really worth $6, except for the fact that a $6 price tag lets you upgrade Farmlands into Provinces. Or Border Village: a $6 Border Village is way stronger than a $5 Border Village than has exactly the same text on it.
Right now, here are some of the interactions:
(1) Upgrade/Remodel/Expand into a $4/$5/$6 card. The combo is that you can do this while keeping the 2 VP victory card. For Upgrade, you'd almost always want to trash the card, because outside of Gardens/Silk Road, it's no help in the endgame, and early on you'd probably want to actually trash the Junkyard. But Remodel/Expand lets you get free Duchies, so that's cool. On the other hand, this would also be possible with a higher price tag. At $4 in particular, Upgrade becomes a lot more useful.
(2) Apprentice to +3 cards. My guess is that this is one of the best combos with the current card. But upon closer inspection, what does it do really? If you have an Apprentice and a Junkyard in your hand, that consumes 2 card slots, for which using the combo will give you 3, resulting in a net gain of only 1 Card. That's not huge, considering that it took colliding two distinct cards in your hand to achieve it, and you don't even get the deck-slimming benefit that Apprentice normally also gives you. Well, of course you can still trash the Junkyard if you want to. But in the endgame, the benefit probably isn't big enough to aim for. It's more of a benefit that's simply nice to have if you had other reasons to buy Apprentices and Junkyards previously.
(3) Bishop to +2 VP. I already expressed my (very tentative) reservations about this particular interaction, and raising the cost of Junkyard would only make that danger greater. So here's a compelling argument not to raise the cost.
(4) Salvager to +1 Buy, +$3. This might let you gain another Junkyard, or push you over the top for a Province, without actually losing the fuel it operates on. That's pretty strong! On the other hand, you're still using two card slots to achieve that, which is a mere $1.5 per card. A couple of Silvers would have earned more money, albeit without the extra Buy.
(5) Trader to 3 Silvers. This is actually a big deal. Maybe better than the Apprentice combo, ultimately. But the window of opportunity for actually using the combo is small: too late, and you won't be able to use the Silvers you get. Too early, and that might mean you bought a Junkyard too early. Or if your whole strategy was to get an early Trader and an early Junkyard and flood yourself with Silver, then you're unlikely to be able to actually USE the combo very much, since every time you use Trader, you decrease the likelihood that Trader and Junkyard will collide again. Moreover, using Trader on an actual Silver nets you two Silvers anyhow, so Trader on Junkyard is a mere one extra Silver. It just doesn't seem worth it unless you can hit that narrow window in the early endgame.
As I said at the outset, I'm expecting Dark Ages to have a card that does something like this. I don't know what form it will take, but I'd take a 60-40 bet that the idea will be there in some form -- along with enablers that would also enable Junkyard. So it might be good to take a wait-and-see approach before making any decisions about what to do with Junkyard.
But based on the current set of cards, I have wonder if something like 4 VP for $6 would make for more interesting combo potential. The combos will be bigger, and it'll be a bigger deal that you don't lose the card's VP. Those are numbers off the top of my head, but you see where I'm going.
