For whom hooks up with whom...I'm saying:

Victor and Kelly (kinda obvious)

Pegs and Muldoon (Muldoon says "no fucking love", Pegs reply "you seem really nice, I'm looking forward to get to know you". Although totally sarcastic hints to future gettins on, and I think it is over between her and Michael and they will move on from their time in the tower)

Michael and CJ. I think they will be the perfect couple, yet won't realize it until the end or close to. They will be too busy leading the fight against the zed's

Riley, unless there are some tall blondes left, male or female, she may be screwed...

Unless season 4 brings new characters, others like Datu probably won't have a love interest as part of their story.