Concept is simple, doing is difficult.
One can see you stop the running action as you wait to land…make the hurdling more like a flat sprint with the arms going front to back (direction of travel)…what is happening is you are preparing for a long flight which is exactly the opposite of what you want when hurdling…the arms are going out to the sides as this is the natural action humans have when they are looking for balance while straddling something…keep in mind, the board is only 3/4″ wide, not 3′.
FYI: IMO your timing is a bit “off” in the photo…the position that your lead leg is and certainly that your trail leg is pretty good but in this leg position your hips should already be “over” if not just past the board…to me it looks like they are still an inch or two behind the board…i.e. this is GOOD as it indicates your trail comes through very quickly (or that you have a really, really long flight time…not so good if that is what is happening; OR you are too bent at the waist in the tuck or hold it too long, open/straighten sooner will help…its a timing thing) but with a bit of tweaking on the synchronization you will find your times will drop dramatically…
Again, IMO, its all the same issue…make your hurdling less like a jump w flight time and more like a sprint with the flight time being the portion of each stride when neither foot is in ground contact. This picture also shows, as you say, you are crowding the hurdle, get in the habit of making the last 2 strides into a hurdle (1H, or others in both sprint or intermediate events) at a quicker pace, this will in effect move you “back” a bit plus a less prolonged flight (from above) will help too.