I'm not gonna lie to you: I was pretty strongly prejudiced against this one from the start. If there's one thing "Back to the Klondike," the Barks story, does well, it's avoiding excess sentimentality; leaving exactly what if anything happened between Scrooge and Goldie as subtext was definitely the correct move. And I sure wasn't expecting that kind of subtlety from the episode, especially in the beginning when it so clumsily telegraphs its intentions: "Bah! If you ask me, this Valentine's Day business is a waste of time and postage stamps!" Scrooge fulminates, causing mass anticipatory groaning in the audience.
I'll say this for it, though: it could be worse. It could be a lot better, too, but the beginning, at least, is well-done. The depiction of Goldie is not half bad; she has a nicely brassy Mae-West-ish voice, and her introduction, as she vamps it up with a parody of "Diamonds Are a Girl's Best Friend," gets things off on the right foot. She's appropriately rapacious, which is important. Then, there's a card game involving her, Scrooge, and the newly-minted villain, Dangerous Dan (any relation to Dangerous Dan McShrew from "The Loony Lunar Gold Rush?" Only in the sense that they're both take-offs from the Robert Service poem), and it, too, is well atmospheric. After that, it kinda breaks down, however--unsurprisingly, the vaguely sadomasochistic bit where Scrooge forces her to work on his stake has been excised; instead, she goes along voluntarily, which represents a rather abrupt and unexplained change in character for her.
Of course, while she's working there they fall in luuuuuv, and the only reason they break up is because the irksome and unnecessary Dangerous Dan steals the gold and makes Scrooge think it was Goldie--as opposed to the original conception, in which any feelings they might have for one another are buried under thick mutual layers of pride and general orneriness.
And then it's the present again and they make up after ol' Dan helpfully loudly proclaims his culpability in stealing the gold, and then it's all happy mush and a widely (and justifiably) mocked ending in which the puffs of smoke from a train form into hearts. One might, I suppose, argue that it was inevitable and necessary for the cartoon version to jettison nuance and subtlety as it does, but I'm not so sure of that--the show has certainly shown itself to be capable of those traits in the past. Objectively speaking, I think it's a fairly well-put-together episode, as long as you have a certain tolerance for the saccharine, but it seems undeniable that making Barks' ambiguous romance into an uncomplicated love story robs the whole affair of most of its richness.
-Here's how modern-day Scrooge and Goldie find a new vein of gold: they're getting all nostalgic and sentimental until they start arguing about whether she stole the gold, at which point she opens fire on him and hits a rock, revealing the gold beneath. I would request that in the future, Ducktales writers, you not do such flamingly idiotic things.