I can tell that you want to focus on hammering out sick double bass licks, which is great, because I too love sick double bass licks. However, if you want to do that, you need to practice with a metronome or to music. I can hear inconsistencies in your double kick work between the feet, and when putting it with the hands you often times fall out of time.
Now, before I sound like a total a-hole, I can tell you the good news. To solve the problems you have with timing one of the best steps you can take is to record yourself and listen back. So you're already doing the right thing. Take things slow and focus on getting the double kick chops up to a point where you are very comfortable with them and then apply them to your playing. Remember, (as cliche as it is) keeping time trumps crazy double bass licks.
