If anyone is interest on the brushes that I use and how I used them here's a rundown:
I use the Dan LuVisi bruspack V2http://danluvisiart.deviantart.com/art/My-Brush-Pack-2-0-370697141
The first one is called "chalk 2" this one I use the less, is a pretty texture heavy brush, I mainly use it for final details on portraits, I can see myself using it in other stuff like props or even landscapes, I think this one unifies everything with a pretty good texture.
The second one is called "Chalky square painting" this one I use the most because is has the less texture therefore its so light, I use for sketching and for blocking all the values and colors. This brush is my favorite and most used one.
The last one is called "Chalk Textured" this one has a pretty cool and heavy texture, I remember I used it on some metal once and I fell in love, I use it lots to unify the values and add and overall texture to the skin.
I also use the smudge tool with a brush called SCRATCHES_V that you can also find on this pack (set to 74% strength) However I think the most important and overlook detail that lots of people missed at the begging is to try to lay down the values to a level that it looks pretty much finished and then I go for the details, I think this is the best way to do it, there's no magic brush that will make all the decisions on values and color for you.
Here you can see an example from an artist I love (Charlie Bowater) on the left there's a blocking of color and value and on the left there's the final touches with textures brushes and some smudging, as you can see the hard part its already done. This not only yields a very good result but it also makes you faster.
Hope this helps.