I have used Finale from the beginning. One thing has never been improved over all these years is the chord and shape designer dialog boxes. It is where you can creat chord symbols and other custom objects. Those dialog boxes look and feel so outdated, it is embarrassing to say the least. Not only that, they are also full of bugs, especially the chord symbol designer one.
What you could change in the chord symbol designer:
First of all, make it bigger.
Make it possible to simply drag each element to the desired position instead of having to give it a numerical value to position it.
Forget about the order of the objects. Why would that matter (previous-next). Just let folks grab the thing they want to move and move it. Double click anywhere to creat a new element, etc.. This is the 21. century, people!
About shape designer:
How about adding colors. But that's not even a priority right now. Make it work better with tool pallets, pinch/out functionality with drag pad, and a more intuitive workflow would be the first thing you should jump on.
Other things that needs to be addressed in Finale:
OPTION-DRAGGING stuff. Finale is the only program I have on my Mac that doesn't let me create duplicates of text elements by simply option-dragging them.
In closing. I could go on and on with feature requests. For example, I suggest you give the entire user interface an more contemporary look.
For example: A toolbox without color? Even during the first 15 years of Finale you had color for all the different tools. What happened there?