It might be because I listened to the audio-book, but the character Skelly almost ruined it for me.
*** Spoilers ***
I also found Count Vidian to be an incredibly ridiculous bad guy. He supposedly got to where he was by using his real identity to forge his own safety reports, but also by having good business acumen. The scene early on where he goes crazy and pounds the guild master to death with his robot arms literally made me laugh at how stupid it was.
I do agree with you that Kanan was really well written. Particularly when it came to his light vs grey struggle. I didn't care for the lack of character development for Hera though. Maybe it's because I'm an old school Star Wars EU guy, but I have a hard time when they use Twi'leks as anything but mercs or slaves. Ryloth is supposed to be one of the traditional slaver planets. I wish the Star Wars writers would come up with another form of alien they could represent heroines as rather than always a human or an alien with head-tails.
I would only recommend it to those of you who watch Rebels and want to know some of the background of Hera and Kanan. They don't really go into much detail behind the early Rebellions organization or, frankly, anything that actually affects the show.