One criticism I have of the current Dr Who adventures is that the majority are one episode - just a few stretch to two. It should really be a cliff hanger serial as it was in the past. I suppose it's a modern day short attention span thing.
I've found quite the opposite. There are the odd two parters, and loads of single episodes, but after watching them all you discover that there is a common story line that runs through them. Although this common story line is usually somewhat subtle, c.f. "Bad Wolf".
Personally, I harbour a dislike of Eccleston's portrayal and his apparent use of the Dr Who character as a vehicle for career advancement: "Play the part, get the media exposure and then quit". Quitting after a single series was just too obvious a move. Also his impulsive characterisation and wildly swinging moods didn't really lend themselves to the concept of a person that is normally in control and a leader.
Tom Baker was also a bit too pompous to be entirely enjoyable. I think most of his following comes from having been the Dr. for so long.
As for Tennent, I thought he was probably the best. Although you can't help but wonder how the other actors would have handled the same scripts. It is, after all, the script and situation that ultimately defines the personality of the characters.
The best modern episode, though, has to be "Blink". The one with the statues ... I still look suspiciously at gargoyles.