I should probably sic the ones I've got figured out in here while I still have power:

Character Name: Liara T'Soni
Age at the Reunion: 65
Backstory I've Worked Out So Far: She's an archaeologist! Which means she gets to put 'Doctor' in front of her name and has just spent a year alone on a dig whilst warding off pirates like woah.
How Your Character Can Fit In: She's probably not been super-chatty with everyone since she's very reclusive, but I'm open to ideas!