While I liked the characters in Treasures of the Heart in a general sense, I felt the book was a tad underdrawn. I was disappointed at how quickly it went along and I felt the loss of any true character development.
Also, I felt I was expected to accept a lot in what was a contemporary novel. For example, Bree trusts Jack awfully quickly for someone she's just met, especially since they're being shot at on the day of that meeting.
Also, I have a bone of contention. If someone starts chasing you and shooting at you with a gun, the logical thing to do is to CALL THE POLICE, not to just continue on your quest in the company of a man you've just met :-). I could accept this more if it had been a fantasy book in a world where this kind of thing was normal, but in the real world? If someone shoots at you, you contact the law.
This was the same at the end. We're expected to accept that, in spite of the fact that he's an ex-navy SEAL, Bree can disarm her attacker with a single move while he has a gun to her head. If there had been a suggestion earlier that she was a martial arts expert I could buy it, but although that is mentioned as being a talent Kristen possesses, there's no mention of Bree having this kind of training. It's a shame, because I felt that would have made the scene work better, at least for me.
And I think a bit more mulling over the moral of the story - greed - with the main characters taking more time to make their decision. After all, I think even Christians would struggle in those circumstances.
If a novel's going to be based in the normal world, I think it needs to reflect it in a more realistic manner. It was still fun, though.