Very well on theme.
At first I thought it was just like Mastermind where any note could be in any order at any position. After finishing the first puzzle and seeing the name of the scale I saw the pattern. That made the puzzle afterwards way too easy since as soon as you have one note in place the others are easily deducable.
My method was as follows (see screenshot):
Guess all A's on the first try, giving me a starting point.
Then guessing ABCDEFG with A in the right spot we got in step 1.
After that we just need to fill in the missing notes with the sharp/half(?) notes.
Unless there is a scale that does not contain A I think you can get the correct solution every time in just 3 steps :)
One of the better games in the theme department for sure !