I didn't see anything wrong with that one episode of TNG with those little creatures, when I first saw it, it was more violent than I expected, but it was cool. I don't see how they could've not killed the people with the parasites in them - Crusher said that if she tried to remove it, it would kill the host. Did they ever continue that story? They said that the creature activated a homing beacon.
It's getting annoying with no crewmembers getting killed, I mean they've got all these problems, they shouldn't really have the ability to handle ALL of them on the spot. I guess Berman's "logic" on this is that since there is no way they could get more crewmembers is by going to Earth and starting over, that it's better to go with that it's more safe back then when it's unexplored and humans could still be amazed just by a giant space rock. (comet/asteroid)
I think TNG had quite a few good parts on action, I remember one episode where someone ended up sinking into the floor and getting stuck there. There was also this one part in one Borg episode, when they cut out a piece of the saucer.