Stage: Dream Forest

The first stage of the Rayman series is a must

Stage: Saffron City

We need this stage back for archive purposes. Saffron City was pretty simple, but was a really enjoyable stage.

Item: Mushrooms

 We all know the two types mushrooms in Super Mario Bros. However, in the Galaxy series along with the New Super Mario Bros., there were many new types of mushrooms. I think we should see a few of these in the next Smash Bros. The mega mushroom could make you as big as possible for a little while, but is much rarer than other mushrooms. The bee mushroom could give you the ability to fly briefly without any limitations. Lastly, the stone mushroom could make you unable to be knocked back, but in exchange you'd be slightly slower.

Assist Trophy: Donkey Kong Jr.

Donkey Kong's son, who has starred in several arcade and NES games, I think just needs a little more time to build up his resume to be a character. For now, he could slam his key at you. I personally would like to see a new DK Jr. game for the 3DS.

Starfy Enemies

 Pearl Sprites seem fairly common throughout the series

 

Jellysquishes seem to be a perfect wimpy and common enemy, but still essential

 Octopults I guess are somewhat similar to Octoroks from Zelda

Taddledogs just flat out look really cool and I want to see them in action

As I said, I don't know too much about this series, but I looked around and these enemies look like the most ideal enemies to use.