I love Voyager because of it's humor most of all. It makes it unique. TNG, DS9, ENT, and TOS all have humorous moments, but VOY really feels the most light-hearted despite being in one of the most dire situations.
Without the characters of the Doctor, Seven, and Janeway I probably wouldn't love it as much as I do. I think the cast had good chemistry. Even if there were tensions off-set, I don't really care because when they did perform the humorous bits, I think they were done really well. It makes Voyager unique.
I also really love that it deviated from all of the pre-defined rules, AQ conflicts (with the exception of the Borg), etc...because they had no contact with Starfleet for years.