Hi and welcome.
a real tee would be an easier reference for you to practice on, because you can see, where you planted. Before you start to move imagine a direct line from your right foot to the target and try to have the right foot land on that line with each step.
You don't twist the hips past neutral to the right and it reduces the amount of power you generate. See what happens, when you pause the body for a while, when the chest points 90 degrees to the left of the target and you pull the arm closer to the target at that time. Faster than you move the arm now. You should be able to get the elbow way past the right side before you straighten the arm. That should be as fast as you can and there is an individual difference you have to check for yourself. Some throw farther with the fastest acceleration of the forearm beginning later than the onset of the straightening of the elbow. You should start to accelerate the arm at different positions comparing distances with the same disc from when the right leg plants to 8" short of the disc ripping out of the fingers.
You don't accelerate the arm really. The arm motion needs to accelerate in the end and the looser the muscles above the wrist, the faster the arm whip. What happens in the wrist and through the fingers to the disc is more complicated and the next step after learning to accelerate the arm. Think of how loose your muscles are, when you try to swat a fly with a rolled up newspaper. You concentrate on being fast. If you have tension in the muscles, you move slowly and the fly most likely escapes. You need to stay loose to get the maximum speed the whack that sucker.
Flat shots need running on the center line of the tee and planting each step on the center line. Anhyzer needs running from rear right to front left with the plant step hitting the ground to the left of the line you're running on. Hyzer is the mirror of that.