Not really rock but I'm a big fan of Bebo Norman's early discs. He doesn't beat you over the head with his message. 

Although there may be some Christian rock which beats you over the head with a message I'm not aware of any.  There is a message but I don’t get the sense that I’m being beaten over the head with it...certainly not what I've been listening to.  I saw Bebo with Third Day a few years ago...very nice performance.  I personally don’t care much for left leaning politics in my music…but that’s just me. 

Here's a mix of some Christian rock for you to check out.  I’ve got a bunch more but this will give you an idea of what’s out there.  A few years ago I had no idea this was out there and now it’s about all I listen to anymore.

Kevin g

The Afters, Beautiful Love
The Afters, Love Lead Me On

David Crowder Band, Rescue is Coming
David Crowder Band, A Beautiful Collision
David Crowder Band, Do Not Move

Third Day, Agnus Dei
Third Day, I Believe
Third Day, I Can't Take the Pain
Third Day, Consuming Fire
Third Day, God of Wonders
Third Day, When the Rain Comes

Robbie Seay Band, Better Days