Sounds like your dog should certainly enjoy her toys! I think you might deserve a lot of the credit with your training for your dogs behavior!
"Unsure" and "Fear Bubbles" are not normal for an otherwise solid dog - at least we have never seen any in any of our many GSDs over the last 40 or so years. "Unsure", less than 100% confidence behavior, yep, in a couple but in our case it seemed to be genetic and could be addressed with solid confidence building training and lots of work.
Our last GSD was absolutely rock solid from the time we took him home from kennel as a 7wo baby. Never a backward step from anything/anybody. Also had almost no "Startle" response to things - loud noise or sudden things. Great dog - the temperament that my opinion is that a GSD should have. And we certainly don't take a lot of credit for his solid temperament - I think that he mostly came with it and we just let him develop and show him what we expected with his temperament and behavior.
In fact, perhaps he might have had a bit too much self confidence as he was a challenge in some ways for a while, growing up.