So I finally after a year of Flying a P3A and P4, broke down and ordered a new Pro Black edition.  Here is my questions.  What filters should I purchase.  I am getting extra batteries.  TB48, how many should I get.  Is there anything that "you" can't live without that I need to know?

First I would run with 4 batteries as long as you have access to a charger.  Obviously, plan your shots carefully as to not waste time in the air and try's not to throw a spent battery back into a charger right away.  Don't want to overheat the batteries.

That said, get as many batteries as you budget allows to cover the most amount of flying time  for your needs.  Can't stop time.

As far as filters, it all depends on what you are shooting, what look you're going for, are you shooting still, or video, what frame rate are you shooting at, etc   So a mix of nd filters if you are  shooting video at different times of day.  Make sure the filter weight corresponds to the lens you're using, or counter weight the filter.

The stock DJI MFT 15mm lens does not have any ND filters available, but some customers have used some universal filters with it. If you choose to use a 3rd party lens, however, most of them have filters that would provide an additional benefit to balancing without the need for a ring.