Well, this was pretty amazing... You most certainly get top marks for mood and audio! I found the controls extremely difficult - but I think that's probably the point. I suspect it's quite realistic and having had no training, I found it tough to get my head around this kind of manoeuvrability. I do agree with a previous commenter that the main character in the scenario would have extensive training, so it would make sense to have some kind of documentation for us as players that in some way provides the information that an astronaut would have received. Trial and error makes for realistic gameplay if _I'd_ found myself in that situation though!
So, I really wanted to persevere and make it back to the station to see the ending... It took me about 2 hours to finally get there! I'm not sure what kind of average you'd expect. I'd spent the first part of the game orienting myself with the station dead ahead, and then firing my thruster to move toward it. Once I became blinded I found that heading toward the station (i.e. with the light indiciating I was facing the right way) wasn't as useful as just paying attention to how the stats changed as I used the thrusters. I'm pretty sure that I came in backwards and upside-down. ;)
I have to say, I was a little disappointed that there didn't seem to be much to my ending... A beautiful shot of the ISS to be sure, but given all of the audio clips and the picture I'd built up of the main character's life and relationships - and given the amount of effort that must have gone into all that - I was surprised there wasn't any payoff and continuation of the story as it were.
You've mentioned different endings... I'm not sure what others there may be. Though I did note down a code that I found no use for. I couldn't see how the code translated to co-ordinates and I'm not sure what else it could be.
Anyway... an impressive and undeniably immersive experience. I'd love to see it in VR. I'm not sure how you could expand on it beyond the jam version, but it could certainly be a part of a bigger narrative game. Great entry. Very well done.