The only thing in my opinion that is holding gaara back is his experience. If he had that gaara would Most Deff probably own or fight on equal footing with all the kage. Yeaaaaah Gaara's sand isnt a good counter for the raikages lightning, Why does that matter ? As iCan recall garra started off with a huge disadvantage against the 2nd mizukage but pulled a victory. I'm sure there is a way for A's speed to be countered, as well as his lightning just like the water techniques of the mizukage were.
In my mind iThink garra could use this Technique to help him with A to slow him down
You must be registered for see links
Every opponent has a weakness, and in gaara's case decoding it isnt that hard of a task. But who know's, iJust Had to say my peace.
Im out.