I'd have to say a Pokemon Fighting game running on a modified Brawl Engine (four specials, a final attack, knocking the opponent off the edge) would be neat.
The game would be based on the Anime, meaning all the playable characters would be ones that play a substantial role in the series, and the stages would be various locales from their.
The starting roster would be comprised of the Main Character DP Roster (prentending if the game came out now). This would equal 19, but there would be 60 Playable Characters in all (from various seasons) leaving 41 to be unlocked. Each character is grouped by their trainer (Team Rocket counts as one) and the Trainer wouldn't come into play except during their PokeBlast (more on that later).
Meowth* (Team Rocket)
Wobbuffet*** (Team Rocket)
Mime Jr. (Team Rocket)
Carnivine (Team Rocket)
Seviper (Team Rocket)
Dustox** (Team Rocket)
*Meowth would use various weapons since he himself is limited with attacks.
** Dustox and Staravia, the "airborne" Pokemon wouldn't actually fly per se, but would always be hovering slightly above the ground. They'd have alot of jumps, but to make up for it low defense.
*** Wobbuffet would only know counter moves, making him "skill character"
The Secret Characters would have a wide array of unlockable methods.
Team Rocket Pokemon
Hunter J Pokemon
Nurse Joy Pokemon
Plusle and Minun (Movie 7)
In Single Player, you have five modes.
Arcade Mode- A Twelve Match Bout against random opponents on random stages.
Journey Mode- The Story Mode, involving a brand new story set in a Mysterious-Dungeon esque world. Sidescrolling, boss fights, and even mini-games.
Stadium Mode- Play a variety of Challenge Games, including Scenario Fights and Target Challenge, and Timed versions of the Journey Mode Minigames.
Traning Mode- Train here.
Advanced Arcade- a Twenty Four Match Bout against random opponents on random stages.
In Multiplayer Mode, you have a variety of battles.
Free For All- A 4 Pokemon Battle Royale!
Tag Battle- Join Teams to fight!
* Wailord Battle (Giant)
* Diglett Battle (Small)
* Slowpoke Battle (Slow)
* Ninjask Battle (Fast)
* Gastly Battle (Light)
* Golem Battle (Heavy)
* Steelix Battle (Metal)
* Shedinjask Battle (Sudden Death)
WiFi Battle- Go online to fight opponents. There are many billboards to show the top fighters around the world, and you don't need friend codes!
Item Pack Mode, you can view various data here.
Radio Player- Listen to BGM's and Sounds
Television- Watch various cutscenes, including some from the Anime
Figurine Collection- Look at the Collectible Figurines you've collected.\
Pokedex- Check out stats on the Playable Pokemon
Poketch- Look at your friend code list, and WiFi Rankings. Also set up WiFi from here.
PokeNav- See various tasks you need to complete for secrets.