Sweet spot importance
I believe Terry has advocated lessening the importance of sweet spot as a goal early on. The skating type drills and then the switch drills are in a way more important to whole stroke mechanics.
Not to dismiss the value of sweet spot, but if you don't have good balance, the rotation can really throw you off. And for you this may especially be a problem due to your assymetry. You can use a less rotated side breath to substitute for sweet spot.
Trying to "master" sweet spot early on has been a major stumbling blocks for quite a few and the suggestion has always been to move on to other things.