Well, I mean, some things were rather unrealistic (BESIDES THERE BEING ALIENS), like the lack of sex drive. Yeah, yeah, it's a kids' book, but they're RIGHT at the age where it's almost guaranteed that the one thing on a boy's mind is sticking it in a girl. Hell, with morphing, maybe the somewhat desperate Marco would go off in some morph and get carried away.
In the years they didn't see him, what did Tobias do? He kept his hawk act up, so did he make a little hawk family?
Definitely should make the "new" series for young adults and up. Not sex scenes all over the place or anything, but with respect to us somewhat older people (I say somewhat because, relative to most people here, I think I'm young). We know that jokes about their genitalia changing/disappearing would be funny. I sure as hell know that Marco would have complained about it almost every time he went wolf. And Tobias, stopping by Rachel's often at night? Psh.