Part of the charm of Doctor Who is that the next actor to play the role after the regeneration, is ususlly cast to be very different from the last.
David Tennant is one of the most popular Doctor's of all time. Over the last 3 years, he's played the part admirably. These are his first two stories, and my biggest gripe is that it becomes obvious that this production team wanted him to fall in love. That's something the Doctor just shouldn't do. Ever. Not with a human. That's the tradition of the show.
The plots are fine, I'm quite a fan of “New Earth” other than my prior gripe.
Good all round effort, but volumes 2 and 5 of series 2 are better.