Lingering shots of Richard Armitage doing nothing other than rubbing oil over his naked body.
Love interest for Bilbo: Thranduil’s little sister (played by Hayden Panettiere), a spunky Elf princess.
More?
Extended car chase sequences
Sauron’s backstory.
A love interest for Gollum; before he turned into Gollum and was plain old Smeagol.
How Elrond is actually Agent Smith and Middle Earth is just a recreation in the Matrix.
Also, a Dwarven musical number where they dance around pillars and pass the Arkenstone about.
It would actually make a good film, or at least part of the film of Beren and Luthien. Won’t happen as the Tolkien estate won’t license the Silmarillion.
Donkey love interest for Smaug?
A wacky sidekick for Isildur that talks in ghetto slang and reinforces a somewhat disturbing racial stereotype.
“Yousa gotta destroy da ring Issy!”
I read this as “a love interest for Sauron” and then I though, hmmmmm
Long, explicit Bombadil-on-Goldberry sex scene.
Follow the adventures of a totally new hobbit and call the movie “The Baggins Legacy.”
I could see them doing a flashback scene about how Gollum finds the ring.
Tragic, doomed love story between Bilbo and a fetching female goblin who he meets in the Misty Mountains, then sees again at the Battle of Five Armies. As they rush to each other’s arms in the aftermath of the battle, Bard will make an unbelievable long distance shot to “save” him.
Tragic, doomed love story between Gandalf & Galadriel (why else would she be stroking his beard in the trailers?)
Won’t there already be a Dwarven musical number when they wash Bilbo’s plates?
Splice in footage from the movie “Russian Ark” for Smaug’s treasure trove scene.
Narration by Treebeard.
You remember the old joke about the Pygmy boy dating the Watusi girl:
“When they were toes-to-toes, his nose was in it.
When they were nose-to-nose, his toes were in it.” 
Beorn’s expedition to the East Pole.
Also, what happened to his wife, his child, and that little blonde girl.
invent an elf character to give Evangeline Lily a job.
Also,adventures of Radagast the Brown.
no, wait…
Elf races?
Dwarf tossing?
Gandalf lectures at Hogwarts?
Flashback telling the story of Golfimbul, the Benevolent and Protective Elder of the Orcs, and how he lost his head and helped invent the game of golf.*
"Iluvatar help us, this really *is *in Tolkein’s book The Hobbit (Well, without the BPEO label). Tolkein was obviously in his “Grandfather is joshing us” mode when he wrote it. There’s a lot of humor in Tolkein, but he manages to make it not actually funny.
They already do, his name is Déagol. “My love” and all. I think I went to the bathroom at that part in the 2nd or 3rd movie, so I missed some. I’d like to guess that they’re still in love, but separated across miles and centuries, but will reunite in the unannounced, fourth Hobbit movie, with some material from “The Precious,” by Nicholas Sparks.
Thread win.
Actually show the dwarves being kicked out of the Lonely Mountain and follow their journey to Bilbo’s in real time.