You have the same approach as me.... 4 steps from the back of the approach. A few standard bowling tips apply differently to those of us who use this approach.
With a 4 step approach, the 'push away' isn't as important as it is for a 5 step player. With 4 steps, you will start the ball at the same time you start your first step... so the timing of the push away is not a big deal. The only thing you might change, is you could start the ball a bit higher if you feel like your timing is off, but it looks good to me.
There isn't a lot you can do about the big leg kick. Look at the video, and watch your power step. When you push into the slide with such a long power step, your leg is going to kick. The best thing you can work on is keeping that back toe on the floor throughout the leg kick. That way you have a feel for what your foot is doing. And in the long run, you will develop a feel for when you do something wrong in the approach.
And one other tip, keep your feet slow. With the long approach, alot of people tend to rush the approach. You will generate enough power in the last 2 steps, that there is no need to rush the first two steps.