Season 1 did actually deal with some of this and managed to establish some arcs. But, they were resolved very quickly or were just absorbed in the events of the show where the crew simply learn to work together because....they simply learn to work together. DS9 was a Marquis heavy show, so I understand why Voyager didn't quite go that far. It's a better show for understating the Marquis elements. But, if they at least fleshed out the origins of people like Chakotay and Torres in greater detail outside of their childhoods, I think we could have had an even more detailed take on the characters and the tension between Marquis and Starfleet officers.