Hi NUGFX,
The visuals seem like a solid start.
I agree with the comments above about kerning etc.
I also strongly agree with Clarke's point about the shading. I've never been a fan of gradients in logo design. It's something that has become popular with the advent of logos only being used online. When physically printed the shading softens the logo and lessens it's impact, even though it might look nice on screen. However, when it comes to logo design 'looking nice' isn't necessarily the aim.
You list a 'clean' look as an important factor. I believe you'd go a long way to doing this by reconsidering the shading.
In the first visual I like the idea of the diamond sitting on the C to make it look like a ring. It's simple and striking. Try nesstling it into the 'Rock' text above the 'o'. Should make the logo a lot more compact without compromising (possibly improving) the original idea.
I'd try using a different font for the tag line too. In use that text is going to be very small, and a font with such heavy serifs will feel clunky. Try to find a minimal yet complimentary font to the main text.
Hope that helps.