When considering that Dodger is named after Jack "Artful Dodger" Dawkins from Oliver Twist and a terrier in the film, you'll realize that he's a Jack Russel Terrier.
Why are the Dobermans quickly subdued with a blanket? One way to test a dog's intelligence is to throw a blanket over its head and see how long it takes for them to shake it off. Considering that Roscoe and DeSoto are considered dense, it makes sense that they wouldn't try to shake the blanket off themselves.
First, this brings up some Fridge Logic: Dobermans are intelligent dogs. But then, it dawns on you: Dobermans are supposed to be gentle, too. The only problem is that it all depends on how they're raised. And don't forget, Sykes is their master; if he can teach Roscoe and DeSoto to be sadistic, even for dogs, he possibly neglected to exercise their minds (aside from being thugs).
It just came to me: Old Louie is the movie's equivalent of the food server from the book, outraged when Oliver pleaded, "Please sir, may I have some more?"
When Fagin writes the ransom note, the ironing board buckles under his weight as he sinks lower and lower.
That ironing board only drops to the level he's comfortable with; however, later, Fagin seems uneasy and nervous when he takes the elevator down to Sykes' office.
Dodger's song "Why Should I Worry?" comes back in the ending. It becomes meaningful as a Triumphant Reprise when one realizes the Double Entendre behind it. The first time he says it, it lets Oliver know he couldn't care less about him. The ending is about Dodger wondering why he should care about Oliver when he knows he's now in good hands? This time is about him and his friends letting Oliver know he has their blessing to stay with Jenny.
It may seem a bit curious why Sykes would lend so much money to a homeless man like Fagin until you consider the incredibly high interest rates loan sharks are notorious for, which may be why Fagin is so poor.
It leads to the Fridge Horror that Fagin wasn't always so poor, and he got to his current state because he borrowed money from Sykes.
For the first half of the movie, Oliver is never called by name; he is usually called "the kid." But there's a perfect reason: Jenny hasn't named him yet!
A small thing: Tito and Francis's shared Establishing Character Moment works better when you notice what Francis is watching. The line "tomorrow, tomorrow, and tomorrow creeps" is from the play Macbeth. Tito complains that the show is boring and wants to watch something with action. Macbeth is filled with action, starting with a plan to commit regicide. Francis is a cultured dog, and Tito pays so little attention to details that it costs him something.
During the climactic subway chase, the way Roscoe and DeSoto die matches their personalities:
Being the more level-headed of the two, Roscoe tried to use logical survival by hanging onto Dodger's cloth until Dodger slipped it off.
DeSoto, the sadistic one, was torturing Dodger instead of outright killing him (holding his paw on Dodger's neck), which caused his death by the same cat he taunted and threatened at the film's start ironically.
Brilliance that could have been. In early development, Jenny was originally going to be Penny from The Rescuers, but this idea was ultimately scrapped. Before being abducted by Madame Medusa in that film, Penny's closest companion at the orphanage was Rufus, a friendly old cat, which could have explained why she would have been so fond of Oliver when she found him.
All those portraits in Georgette's bedroom could simply indicate she has many admirers (if all the dogs scampering below her patio during her song notwithstanding), but she's also a prize-winning show dog. It'd be safe to assume that she'd been matched up with plenty of studs who were also high-bred champions themselves.
Why does Sykes use attack dogs despite having a gun? Body disposal — if nothing but a few gnawed bones are left, there's much less for the police to go on if they investigate.
He snaps his fingers a second time to call his dogs off; them ripping into you is another persuasion method.
When Sykes sics his dogs on Fagin and Dodger, he casually resumes building his model ship like nothing's happening; he's likely done this so many times he's numb to the violence.
Why does the gang assume Jenny taking Oliver in will get him mistreated? Because as street mutts hardened by a life of crime and hardscrabble, cruelty and neglect are likely all they've come to expect from humans. Even the film's more sympathetic version of Fagin, as well-meaning as he is, still forces them to commit petty theft on his behalf.
The film probably doesn't mention it, but older viewers will get chills when realizing Sykes has many ways to make money off of Jenny if her parents don't pay up, and none would endwell for her. It doesn't help that she's so precious, either.
The film treats Georgette's breaking of a nail as wimpy and a sign of her being spoilt and pampered. I Broke a Nail is a discredited trope - but it's especially justified why she would scream when it's broken - when a dog breaks a nail? It's bloody. There is a reason dogs' nails get filed off when cut.
Imagine being Winston. You learn the child that the parents entrusted to your care while they're away had snuck out of the house and gone God knows where and why. Then some mafia-connected criminal calls, revealing he's holding the kid hostage to ransom their life. If they ever found out, Mr. and Mrs. Foxworth would undoubtedly have the same reaction.
Fagin's timely arrival prevents Sykes from siccing his dogs on Oliver and the other dogs. However, if Sykes did snap his fingers, would Roscoe and DeSoto have attacked Jenny, too, despite Sykes still wanting the ransom for her? Or was Sykes going to waste her anyway for trying to escape?
Even if Jenny's parents paid the ransom, could one even trust Sykes to keep his word and release Jenny? Despite having many possible chances, Fagin, clearly out of fear for his life, hadn't gone to the authorities about Sykes. However, there's a definite high chance that a scared child would blab about Sykes the first chance they got. Plus, Jenny saw his face and his base of operations and heard Fagin mention Sykes' name as he kidnapped her, probably enough information for the police to use. Someone cold and calculating like Sykes surely wouldn't risk letting a potential loose end like Jenny go, even if she swore not to talk.
One that seems to go over some heads: During their final battle, DeSoto isn't just pinning Dodger's neck to torture him. Look at how close the tracks underneath get to Dodger's head. DeSoto specifically has his paw planted in a spot that forces Dodger's head back and keeps pushing down on that foot until he's knocked off. DeSoto is trying to use the tracks to rip Dodger's head off.
Fagin's Door Dumb moment reveals that an exterior door to Sykes' warehouse opens inward, not outward. The warehouse is not up to fire code. Either Sykes is negligent, or he bribes anyone who shows up for inspections.
If Jenny had been Penny from The Rescuers as initially planned, Penny would've been a double kidnapping victim and survivor saved by cute animals. She'd escape Madame Medusa and Mr. Snoops and do the same with Sykes. The poor girl can't seem to catch a break.
