Yeah, that sounds like a good idea - that maybe it happens to Ellie (unless any of the others particularly wanted to do that), as it could add quite a nice element, that she is trying to help the others, but possibly at the expense of her own time. Perhaps a small leak or something in the oxygen systems - like your breathing time remaining suddenly starts to go down quicker or something. 

Also a feel a tad like my lack of knowledge is letting my detail down a bit, but trying to research as much as possible. 

Perhaps Viktor comes too but is free floating somewhere, and attracts attention with a light on his suit or something - so a character with thrusters has to risk leaving the relative 'safety' of what's left of the station and 'aim' to get him without missing. I'd imagine the thrusters have a limited fuel capacity as well?