I've used the same method as you for a very long time, though personally, I found that reducing the contrast in the woodgrain and overlaying a photo of a real wooden plank would increase the realisticness and quality of the texture. But that's just me. Also, you'll have to play a bit with saturation and hue. If you take a look at my work you might be thinking "What's the guy talking about, his wood doesn't look very realistic at all". That's because I havn't gotten around to creating a single piece yet with the intention of it being realistic
I always use a brownish colour and go a bit more for style rather than it being realistic.. but, reduce the saturation of them and play a little with the hue and you'll gety a realistic wood. Also, it's important not to use too many overlays etc. for these kind of things, or you'll end up with a very brown and messy texture. Seeing as it's not what you're after
Cheers!