Also let me say that I absolutely love this game. Me and my girlfriend play it all the time, and have a great deal of fun doing so.
For a while now though I've been a little annoyed by how the items in SuperTuxKart look and feel. They feel like a random collection of junk, implemented apart from eachother without any overall design. I know this is partly true, cause I've seen the introduction of the swatter and the rubber ball. Don't get me wrong, I like how all items behave, I just don't like their cosmetics.
Let me list all the items currently in use:
Blue boxes
Bananas
Nitro
Bubblegum
Cake
Plunger
Bowling Ball
Parachute
Anchor
Bomb
Swapper
Rubber Ball
Swatter
I think these items need to be rethought to make for a more cohesive whole.
With Auria's proposal of a story mode, I think we should take a look at the story behind the original SuperTux game (if you don't know it or haven't played it before, look it up! it's quite entertaining) and what parts of their gameplay you could reuse in STK.
In SuperTux, Tux (obviously) is the main character, a penguin. He has a girlfriend, a purple penguin named Penny (of whom we've all been reminded recently by a person nicknammed Juliet120STK). At the start of the game, Tux's girlfriend is kidnapped by the badguy, Nolok, whose kart is in STK already. Tux then goes on a quest to find Penny and defeat Nolok, starting off on the South Pole.
The game features several badguys, some of whom could replace some items to make the game more cohesive. Even if you think the following items are a bad idea, I hope you will atleast discuss the possibility of overhauling the items, maybe think of other that will better suit the SuperTux universe.



Some other badguys from SuperTux:



Ofcourse, if you decide to go in this direction, a whole lot more items could come to mind that fit this theme.
I hope you will consider my proposal, and even when you don't like these items per se, I hope you will rethink some of the existing ones anyway.
Regards,
Joost
P.S. I'm fairly proficient in Blender, so I could help design and model a lot of them before you reach milestone 0.8.