I have a few ideas, just off the top of my head, about how various characters might be involved in the mission Derv and I are GM'ing, even if only tangentially (Mosis made some good examples, but there's a couple other things they could do, too). So if people need help getting involved in the RP, Derv and I should be able to help (or provide ideas, at the least).

Also, a lot of the characters have one or more persons interested in finding them or harassing them, so you could use one of the background stories and check with the RP'er playing the character to whip an idea up. Or, following Mosis' earlier idea, involve them with one of the other new characters.

One last thing, the Tyrus is a pretty nice ship, a turian stealth prototype. If any shady black market dealers caught notice of it, or the turian government, or most anyone else, they might be on a hunt to get it. The new character could somehow be after that.