Use a standard MacOS toolbar for your toolbar instead of rolling your own, it looks out of place.
Think more MacOS style would also instead of having that weird modal toggle at the top between creating and opening just have dragging to the dock icon or File>Open opens one, and File>New creates a blank one.
Think more MacOS style would also instead of having that weird modal toggle at the top between creating and opening just have dragging to the dock icon or File>Open opens one, and File>New creates a blank one.