I am also a long time follower of the drafts of parts 61 and 91. I was at the CASA FLOT 2003 conference with many others when this subject was debated. I don't think that parts 61 and 91 will be implemented in my lifetime so I have lost interest.
The current rules provide for a person to teach aerobatics (but not spinning) without an instructor rating - I am aware of one person who does this, with a CPL.
I am not aware of any PPLs who could issue low level aerobatic approvals. Some could conduct the test and recommend that CASA issue an approval.
I did my CPL and instructor rating late in life, after nearly 30 years of private flying. The effort I put into getting the CPL contributed not one iota to my ability to get through the instructor course or teach the PPL syllabus, aerobatics, spinning, tailwheel etc.