What would an Open World SC RPG game look like?

I was thinking what would an Open World SC RPG game look like!

What main character would you want, that the story to be about: Nova, Raynor, Kerrigan, Zeratul (Can you imagine 1 for each, oh my Lord!)

What would the story setup be?

Nova is captured by Valerian, and she is forced to do a mission that she thinks is not the best thing, to say the least, for the future of the Dominion!
In parallel a revolution starts in the Dominion!
Also there are zerg attacks on some terran colonies, and maybe protoss joins in with their never ending Crusade!

(and of course all of your decisions affect the outcome of story, with multiple game endings, all of that RPG good stuff)

Would you like a complete new character in the SC2 universe?

Please tell me some of your ideas!