Let's compare official set 9469 with MOCs that have been built over the years with the same theme. Here are just a few variants of Gandalf's cart (click each to find the original source). I like how Nathan Wells did the fireworks. If you look close you'll see that one of them is topped with a dragon plume. He also made Frodo look shorter in the seat, which was a neat trick.
Cyin's variant is also nice. He includes the fact that (from "A Long-Expected Party") "When the old man, helped by Bilbo and some dwarves, finished unloading..."
I found several other variants that were all quite similar. Wookie Bounty Hunter uses door elements to get a nice shape to the cart.
Both Skalldyr and Gandalf the Grey (Wow! I didn't know he was an AFOL!) put the cart in a large context, including details like a hobbit hole (Bag End?), children chasing after the cart, and fireworks going off (which, btw, is the opposite of the book, but oh well, it made a nice note in the movie).