How would you make it?  For example (3.5), how would you handle spell durations (rounds vs minutes) in terms of game time?  Would you have the game always tracking rounds?  Would a certain amount of time always pass in between battles?  Would you follow the turn-based format or attempt real-time?

It's harder than you think.

A huge sandbox game, where you can do anything. But it's all based online, has similar community features to Halo. Characters are Mii and it can be used to make movies with friends that are stored on the extra storage.

NIS like game with epic story, many sidequests and helluva leveling madness....
That's a game of my dreams. No limit in stats and being constantly challenged* (something like a system from FF VIII where enemy is leveling with you)...I could play such game forever.


*No limits in stats....nobody has done it yet, not even Nippon Ichi Software, but I hope such limit will be PWNed someday.

Wii Storage.
A collection of minigames that tests how fast you can fill up the storage in this extra perephrial.

 I'd go with real time exploring with turn based battles when combat was engaged.  Actions take a while to perform before you get your roll to go with the time multiplayer wise.  If everyone in a multiplayer game is either doing an action that takes time or resting for a set period of time, it jumps ahead.  (For example if everyone is crafting stuff that's going to take half a day.)

as for rounds vs minutes it's just a matter of calculating how much time passes in a round. 

For example D&D like game i've played that focused on a few people fighting at once has each round calculated at about 6 seconds.  (Since initative is to decide who goes first in what is basically happening all at the same time, the number of characters and monsters moving per round is irrelevant.)

So if you had a spell that lasts 20 rounds... it would last 120 seconds.  Each round woud take 6 secodns off the 120 seconds it lasts.  After the battle, it switches back to real time, and the the time counts off just like it does in real life.

I'd make a game where you can update and edit your Mii's (Clothing, personality, etc.). Then you'd give them an enviornment (like a personally designed Mii City) to live in, and send them off to a friend's Wii City to cause havok! Random Mii's would enter your console carrying out preset owner's instructions and stealing your personalized items. Weather (with a Wii Weather Channel option) and location would affect your city too. Sorta like a Wii Animal Crossing! Cars, houses, and, Wii Ware games would be downloadable too. Toss in some DS connectivity for good measure. It'd be a monster hit!

............or I'd make a mini-game collection. Those are cool too.

I would create a game called: Super Legend of Metroid Kart Bros.

Its bassically everything we love in one package

So would you see the game being more like Tactics or Arcanum/Fallout? 

Honestly believe it or not i haven't played Arcanum or Fallout. Just Wasteland so honestly i'm not sure how to respond. The Fallout series is one of those games that's on my "must play" list that i keep forgetting about

I'd have the battles happen on the actual same map you explore.

It allows for a more seamless transition as you could use a non grid tactics system like Phantom Brave for movement that measures feat even better then a grid would and use the same terrain and graphics for exploring that you do for the battles.

Allowing for things like the splitting up of the party easier for exploring multiple paths at once... splitting up to lure enemies etc.

While within the interface everything works exactly like D&D.

 A-FUCKING-MEN!