This was actually one of my greatest disappointments with the game... Like, what was the point of sending someone mail when you're already in their town?? You could just give them the gift and then type what you had to say in the chat.. So silly.
Your other ideas are really awesome too! One thing I wish is that the villagers had more personality. I want them to interact with the environment, actually get mad when you refuse to do something for them and hold grudges for a few days. When they come over, I want them to open drawers, check the fridge, turn on the TV and sit down for a bit. I love the way the villagers are in HHD. If they implemented that into ACNL, it would give the game so much more life. Right now, I see the villagers as decoration for the town. They're cute to look at, but I don't really care about talking to them anymore. Everything they say is repetitive and each personality shares the same dialogue.
I also want a dedicated toolbox so that my mail isn't always full.
I want a lot more storage space. Upwards of 2000. As it stands, the gap between storage space and amount of unorderables in the game is insane. For a game that encourages collecting, they don't make it very easy..
More mannequins/allowing mannequins to be dropped and traded. I want to store certain outfits together so I don't have to look through my storage for all the matching items.
A way to distinguish items in the stores that you have already catalogued without having to check the machine. Perhaps an icon?
I want a way to skip dialogue. Everything is so repetitive and long winded when doing things like shopping, selling, going to the island, etc. It just makes everything so tedious and dull.
I could go on and on, but I don't have the energy, lol.