I don't think that T'yrssa is a slacker. I think that in order to be a slacker you have to actively decide not to do things, and try not to do them or do them in a careless manner. She seemed quite the opposite; she had passion that wasn't focused or directed in any direction and as a result she couldn't keep her personality under control. That'll probably stay a character flow of hers, I Imagine. I did think that her free-spiritedness was over exaggerated a little bit, but that's sort of one of the dangers that go along with character introduction stories.
I think that Picard's been half-consciously mulling over thoughts about having a family for a long time. "All Good Things" made him really look at himself and where his future was leading and then in "Star Trek: Generations" he lost all of his blood relatives. Also, when he was in the nexus, the nexus gave him a world in which he had a very large and extended family and although he was very confused at what was going on, he didn't seem to be against that. I think the bigger step is that they actually let themselves have a relationship with each other and put the past -- Jack Crusher -- behind them.
While I'm at it, I think the Picard/Crusher things in the new TNG books are the best elements. Moving the TNG world forward is a different task from the DS9 world. The DS9 had so many plot lines lingering and so many conflicts built into the series that it's easy to come up with new plot lines. Well, easier, at least. TNG on the other hand was episodic in nature and it pretty much wrapped itself up in All Good Things and Nemesis. But to have Picard and Crusher move forward with their relationship is wonderful character development. The same captain who showed up in "Encounter on Farpoint" mumbling about how they used to let children and families aboard ships is now at the beginning of starting his family.
I also disagree with your "living universe" comment. I know what you're getting at -- star clusters and rifts and planets have a funny habit of turning out to be sentient in the Trek world. I thought that the Noh Angels had quite a bit of personality. It was child-like in the way it had curiosity over the creatures that came to it but it also had wisdom in that it didn't jump onto one side of the Borg/Starfleet conflict and instead tried to figure it out for itself.
Ironically, or Maybe not ironically, I think that Greater than the Sum of its Parts is greater than the sum of its parts. It has some faults, but in my view it had more positive stuff than negative.
"The ship rocked again, sparks flying from the consoles."
I laughed out loud when I read this. I thought to myself, "What, is this a Voyager book I'm reading?" X D