I'm really trying to advance my knowledge of music theory beyond mere book knowledge. I'm a fairly decent guitar/bass player and have some theoretical knowledge. Any critiques of the following would be greatly appreciated. To keep this in the practical realm, let's take a 12 bar blues in A. The goal is to solo over the changes. Now, when soling over these changes, I tend to think in terms of specific scales and certain harmonic notes. For example, I could play the A min penatonic and stay pretty safe. I could also change things up and play the A major penatonic. To advance the ball a little more, I'm starting to play with the placement of the major and minor scales within the A-D-E progression. Now to expand this, I start thinking about the notes in the chords. For example, I'm starting to focus on playing a A penatonic over the A chords, D pent. over the D chords, and E pent. over the E chords. Here, I am focusing on the root of each chord. I could also just play major/minor arpeggios over these changes. Could I also play off of the other notes in each of these chords? For example, C# scale over the A chord. Scale wise, I start, like many guitarists, to get a little uncomfortable moving outside the penatonic structure. In the A blues progression above, I know that I could play the A major diatonic scale and perhaps the A minor melodic. Couldn't I also play any of the modes of the A major scale over these changes (say E mixolidian-I think that's right)? Also, couldn't I play different major scales over each chord? Including the modes of these scales. I'm assuming that one genrally plays the modes of A in A, rather than say the A mixolydian scale.