That's great. Unfortunately it means absolutely nothing if you can't retain decent staff. The other issue to keep in mind is that in a small area, word gets around quickly as to who the good and bad organisations are to work for. If you think Mary isn't bagging you out as a boss to all and sundry, you are deluding yourself.
I think you are still underestimating the importance of sorting out your approach to staff matters. Okay, so you won't change in terms of your personality. Given that, you need to do one of two things:
1. You either need to completely automate the billing aspect, and outsource the overdue matters, so you don't have any staff; or
2. You need to completely outsource your staff management, including invoice double checking, chasing up on insurance matters, etc to a practice manager person/role. The person in this position should give you an update every two weeks (we sent out X invoices in the last fortnight, Y% of our overdue bills have been paid, Z insurance matters have been called 3+ times and are now being sent to the debt collectors/lawyers to chase) and that should be the sum total of your interaction with the staff, other than the usual friendly pleasantries of 'good morning' etc.
If you don't do one of these two things (and I can imagine number 1 being extremely difficult to do in practice) then you will continue to lurch from crisis to disaster.
It's up to you.