Since OP seems happy to pay for the vids, I think a sub to Groove3, supplemented with the SWA vids for X2 or Sonar 2015 (Can't seem to locate the one for X3) would give him a lot to chew on.
Also recommend the advanced workshop tutorials (especially the one on Drum production - good stuff!) in the CW store.
Finally, YouTube has quite a few Sonar training vids. Most are intro-level, but there are some user-made ones that are pretty detailed and great for picking up workflow and technique tips.