You're in luck then because even Harry Kim wasn't completely one-dimensional and managed to contribute occasionally valuable things!
As I said before, it doesn't necessarily 'excuse' the series. But I've watched enough television (or rather, used to) that I can positively compare Star Trek: Voyager's treatment of its full cast to the majority of television shows I've tried out. To that end I will still say that it 'passed' and I'm not lording over it, I'm merely stating that compared to the vast majority of shows on television it handled its cast decently. That is my opinion of course; YMMV.
What does this mean for me? Well, between the characters that were given the most attention being my personal favorites anyway, the often-at-least-serviceable plots and the occasional 'heavy thinking', I have a series I can safely call worth watching.
Your thoughts may not echo my own in any shape or form.