My initial thought on White's 9th move was "what about Ba3?" This fits in with your idea of hitting d6 and it seems to give Black some things to worry about. I tried a couple of engines on this position and they both liked 9.Ba3 eventually, and give White roughly a half-pawn advantage.

My question is this: as amateurs, why would we like this line as White? I've given up a pawn in order to get ... what? ... an isolated c-pawn on an open file? The compensation had better be pretty good! But you like it and are comfortable with it ... so play on! (But I'd say look at 9.Ba3 here in this line. Imagine those two Bishops pointing at his 0-0. ) By the way, I think you are right to believe there is value in learning how to play this line.... It seems like there ought to be compensation here (based on the opinions of masters and chess engines), so learning how to play it should be valuable.

So how to answer 9...Qa5? One of my engines suggests 10.Qb3. And why not? Everything is defended and it gets the Queen off the back row. Plus ... 10... 0-0 11.Bd6. I like the looks of that! (and the computer evealuation is +0.44). I can't find anything helpful in my database.