There is a technique which greatly increases Yosuke's already impressive air mobility, which is called "gliding" by the Japanese. Basically, it involves doing an air dash, cancelling the air dash into his jumping 2B, and then kara-cancelling into the side swap (A+C). The input for an iAD glide looks like this:
966, 2B~A+C
What happens is Yosuke will maintain the initial movement speed of his air dash and will dive down much quicker than he normally would from an air dash. An iAD glide at the lowest possible jump height will actually come out so quickly that Yosuke can't even follow up with a jumping A (the normal follow-up to a glide since it hits on both sides of Yosuke). Most of the time, it is actually more practical to do a delayed jump or super jump before gliding, as you will have a bit more time to input the appropriate follow-up. He can also air block once the 2B~A+C part has finished, greatly reducing his vulnerability while air dashing.
Mastering gliding will greatly increase your options as a Yosuke player, and I highly suggest anyone looking to pick up the character should take the time to learn this tech. It is ridiculous how quickly Yosuke can be on the other side of the stage by using this, and he still has access to all of his other air options afterwards, so there are tons of ambiguous cross-ups and other shenanigans that become available to you. If anyone has questions about gliding, or wants guidance on how to perform it consistently, feel to free to ask and I will extrapolate.
EDIT: Here's a video link showing footage of how your fingers should move when gliding: http://www.youtube.com/watch?v=j0KjX22Z_pY&feature=youtu.be