Okay...mainly so I can get this started earlier: People who don't have characters will be in a second group (that includes you, [@Mistiel], since I see you're viewing this thread as I'm writing this). One group of 10 people is hard. Two of five is easy. Plus...this group of 5 is tightly bound together.

The games would be in the same world, and both would be consistent - if something happens in one game, it happens in both. May hear rumors or see the effects (if the two groups are close enough), even.