I agree with what sps300 said. Watching the video, the footwork seems to be the biggest issue, which will screw up timing and can screw up the swing. Here is what I would do:
1) Definitely use the 1 step swing drill that was already mentioned. This will help you become more relaxed throughout all parts of the swing. If you muscle the ball, it will hurt consistency. I do this drill from time to time if I run into a slump or if I notice any issues with my swing being off. It was one of the first things my driller/coach worked with me on 2 years ago and it definitely does help.
2) Practice with the footwork. The thing I noticed is you have a huge drift left when going into the 1st/second steps. I would practice walking straight. I think the footwork issue is causing your swing to go behind the back, which is one of the reasons the swing is being thrown off. If the footwork can be corrected, then that will help you with the swing/timing.