These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Is Cratchit really the hard-working, underpaid Woobie that everyone thinks he is or is he really just such a lousy bookkeeper with absolutely no productivity on the job and has such a huge lack of skills that absolutely no one would hire him to the point where Scrooge did so out of mercy? Businessmen want to hire skilled workers and pay them what they're worth. If Cratchit really had the necessary skills he could have, you know, found the same job under another employer. Not to mention he already had a few kids who were capable of working.
Is Scrooge really the uncaring miser that everyone paints him out to be or is he just a skilled businessman who is the only one with enough mercy to hire an unskilled louse like Cratchit and paying him what he deserves while deciding what he wants to do with his own money despite the entire city trying to steal it from him in a wealth redistribution scheme? The story isn't about redeeming Scrooge; it's about getting into his wallet.
Also the Ghosts in general, is the Past another Good Is Not Nice spirit trying to teach Scrooge about his past, or a JerkassComplete Monster who really loves to exploit the flaws of Scrooge's past and in some versions show what he could've had if he was not greedy; pushing him away from loving Christmas due to regret, and enjoy it as he/she/it invaded his mind
Anvilicious: But good! (Apparently Dickens even considered "The Sledgehammer" as a title.)
While the moral of charity and giving is obvious, more specifically, the novella was meant as a Take That to Thomas Malthus, whose warnings of overpopulation resulted in laws that Dickens hated because he felt they hurt the poor.
Complete Monster: Largely avoided in the 1951 version. Scrooge is cold, unfeeling and miserly, but he's not a total villain (as he is in other adaptations). About the closest he comes to true villainy is the way he looks rather pleased to inherit the home and possessions of his late, only friend Jacob Marley.
Old Joe definitely qualifies; he takes almost sadistic seeming pleasure in pawning the valuables of a deceased person just to make a quick buck, and laughing in the face of the dead about it. Even a pre-Heel Face Turn Scrooge is described as being utterly disgusted with his actions.
Crowning Music of Awesome: So, you've just finished watching the Zemeckis adaptation and the ending credits start to roll. Unless you were paying attention during the opening credits, you probably weren't expecting Andrea Bocelli to suddenly throw down an incredibly epic version of "God Bless Us Everyone".
As well as nearly half the movie's soundtrack, especially during the eye popping aerial shots of the town.
Fridge Logic: Why was Scrooge surprised to find out that he would die alone and hated? He seemed aware of how poorly people thought of him.
Why was Scrooge, of all people, given this special chance for redemption? Specially if, as Marley claimed, Scrooge's chains (sins) were heavier than his.
As for why he seemed surprised, it's one thing to think to yourself, "nobody likes me and I don't care", and actually seeing just how little your death affects anything, and how, if anything, his death more or less makes the world BETTER, since he's not around to ruin people's good cheer anymore.
It Was His Sled: Granted, it is pretty obvious how it's going to end.
Magnificent Bastard: Scrooge and Marley earn this in the 1951 version. They offer to bail the Mercantile Association out of the debt caused by Jorkin's embezzlement, provided they'll be allowed to buy up 51% of the total stock. They'll only save the company if they can become the company, and both look really pleased about it.
Strawman Has a Point: Scrooge's comments about the workhouse may seem very harsh, but the workhouse was intended to be a really bleak place and a last resort, not a place that was nice to be.
The Ghost of Christmas Past in particular tends to get hit with this. This could be because the description in the book is extremely difficult to depict visually; the first paragraph of the description is fairly doable, but the second paragraph...
"... its belt sparkled and glittered now in one part and now in another, and what was light one instant, at another time was dark, so the figure itself fluctuated in its distinctness: being now a thing with one arm, now with one leg, now with twenty legs, now a pair of legs without a head, now a head without a body: of which dissolving parts, no outline would be visible in the dense gloom wherein they melted away. And in the very wonder of this, it would be itself again; distinct and clear as ever."
Uncanny Valley: The land from whence Mr. Zemeckis draws his CGI characters.
There was some improvement over his previous efforts (The Polar Express in particular), but he did tend to re-use faces for several characters (compare Fezziwig and Bob Cratchitt), and in one scene (in the future, where the Cratchitts are mourning Tiny Tim) the eldest son's face freezes after he's done with his lines.
Bob is more of he Iron Woobie variety as he manages to maintain a relatively positive attitude despite his own personal sorrow.
What The Hell, Casting Agency?: This blogger points out that pretty much every version of the story that gets told with existing characters has one in-story character that there's no good fit for, and one actor-character that there's no good role for, so they just squish them together.