I have thought about that, what if I somehow was on Voyager (or other Trek shows). What would I do? I have a psych degree and Voyager didn't have a counselor (the Doctor did act as a therapist, but can you imagine how awful he'd be at it?). But my training would be woefully out of date for Starfleet. I'd probably just have to chop vegetables for Neelix to earn my keep. I'd probably be a serious holodeck addict with Barclay lever attachment issues.
When I think about being aboard Voyager, I never actually think of a position to be filled, I just think of being there.
I would most probably serve on the Bridge. No idea in what capacity but I prefer the Bridge simply because most of the main characters are there, including my role model (Janeway) and the love of my life (guess who it is ... here's a clue: his first name is Thomas and he seems to be the only person with a middle name, which is Eugene, LOL!

). Also, I strongly suspect that when nothing out of the ordinary is happening, the Bridge must be a place of (practical) jokes 24 hours a day ...

I am a teacher and although I guess teachers are not so much in demand in the 24th century any more, it does seem that Mrs O'Brien managed to set up her own school on Deep Space Nine - with what success is an entirely different matter altogether. But like I said, I'd most probably serve on the Bridge, which means that if I lived in the 24th century and Voyager existed in reality, I would most probably not have become a teacher but would have trained at the Starfleet Academy.
As for holodecks, I can imagine that they can cause an addiction - mainly because if you're lost in space, you can't just go to a real theatre or any other real place of entertainment. You are actually forced to make use of holodecks and although we've never seen proof of this, I suppose that sometimes there must be issues relating to the holodeck use simply because most people would like to use them in most of their free time and if my memory serves me right, there are altogether three decks available only. My favourite programme would be no doubt Leonardo da Vinci, which I would like to use together with Janeway.
For more excitement, there's always Tuvok and Tommyboy's insurrection programme, which they have hopefully completed in the meantime, and for relaxation one could always turn to Neelix's holiday programme, which seems to be a pleasant enough place: