You've got a good physique. I wouldn't classify your legs as 'huge', but they have good shape.
Either way, getting ripped is all about diet, which you either know by your ab video, or you just have good genetics. Some people just hold fat more in certain areas than others. Some have more cuts/striations in certain areas and others don't.
Since you're in single digit BF% already, I would say maybe increase the rep range on the extensions, but don't leave out the big lifts either. How damn lean are you trying to get anyway? Are you competing? If not, walking around at very low BF% is not very healthy. UNless it comes naturally.