1) Bestiality. Well, Julie at least wants you to be able to date the animals, because, disgustingly, it seems that her character was able to develop romantic tension with several of the characters from Animal Crossing Wild World (DS). The idea is that you can go on dates with your tick-speckled creature of choice, wasting your money on frivolous activities and gifts all for the ultimate goal of scoring (new furniture, that is).
2) Now that you can go on dates with our closest mammalian cousin, Julie would also like the inclusion of a restaurant, where you can wine and dine them. The neat part about this idea is that you would have no control over what they order, and they could potentially get the most expensive item on the menu, which you would then have to pay for or suffer eternal embarrassment.
"I will take your most expensive item, stuffed with your second most expensive item."
"Very well sir, lobster stuffed with tacos."
3) The letters you write filter randomly throughout Wii-dom, popping up in other people's towns without warning. Look, I already write sexy and/or disgusting letters to my animals (which they happen to love), so I might as well share them anonymously to an underage crowd.
4) Bring back the playable Nintendo games!
5) An enhanced (well, let's just try for functioning) multiplayer experience. I want to see multiplayer games, dammit! There wasn't really a pull for me to invite my friends over just so they could shake my trees bare and s l o w l y type out two-word messages. While that may be a birthday party for the developers at Nintendo, I was bored out of my gourd. Let's see competitive fishing, fruit fights, a larger assortment of traps, and full-on roman gladiatorial combat.
6) A tradeskill system. Since you're already combing the beaches for shells, why not please every pink-shirt-and-popped-collar-sporting animal by crafting a shell necklace! Tom Nook could buy these creations off you for a pittance, which would keep you from starving for just a few hours more.
7) Julie wants more Nintendo cameo costumes; for example, Diddy Kong's cap, Link's shield, Wink Baufield's ship, and the Phalanx (her favorite accessory of all time).
8) In addition to the bones of dinosaurs, it would be great to uncover the twisted remains of foul play from time to time; then you could move from house to house, looking for clues about the identity of the killer. It'll probably always be Pee-Wee, the ape, and since you can't really blame a gorilla for murderous rampages, he'll always escape jail time.
9) Motion control insanity! I want you to have to dig (with perfect form) every hole, the undertaking of which will cost you about 15 to 20 minutes of real time and sweat. Want to upgrade your house? Be prepared to hammer in every nail! Want to walk to the next house over? Strap the Wiimote to your leg and hoof it over there!
10) Julie would like more holidays. The animals need to celebrate VE Day, all bank holidays, Bowling Day, and National Talk Like a Pirate Day.