It's a hard question (I'd like tooo many things, that are maybe more likely in a wii/wii version than in a console version):
- I'd like a larger town. Far larger. Like the gamecube version, for example, but without the acre system (yuck!). Maybe a town, a shopping area and a countryside area, using the train to travel between them. Or maybe a car or bike your character can use. That'd be soo cool! Also with customization options!
- More villager types, with the possibility to include other human people as villagers (like in The Sims), but not all of them. Otherwise it'd be a bit boring. I would add the following animal villager types: pangolins, hedgehogs, raccoons (hehe), dinosaurs, insects (specially butterflies, ladybugs and bees), platypus,.... I'd also add the chance to have extinct species as villagers, that'd be very educative and cool at the same time. For example : some birds, dodos (ooh, that'd be soo coool!).
- More customization options. I'd like to be able to customize skin color, add tattoos, birth marks, etc. Also, a higher number of furniture sets that are possible to customize. More ores.
- More locker space. If you have, let's say, 3 or 4 sets of drawers, then you should have 3 or 4 different areas to place different stuff, and not a shared one!!
- No grass erosion. Possibility to choose a specific grass pattern, or what's more, to design your own grass pattern!
- Longer cherry blossom trees season. I feel it's way too short....
- More public work projects. Also, when choosing their placement, being able to pick a specific point without Isabelle complaining about space!
- As for villager personalities, I'd make them more real, and the dialogues less repetitive. More like in Wild World, for instance. Crankies would be real crankies, lazies would be lazies and so on.
- Villagers being able to dig holes, fish, catch bugs and more importantly, being able to gather their own fruit!