Phal: should I cut more roots?

[Pollicino]

Hi guys,
I'm Irene. I've been reading this board for ages and I know the very basics re-potting a Phal... but when it's time to put it into practice... Well guys, I need your help.

This is a Phalaenopsis from the grocery store that has been sitting in a sphagnum core for too long. Please, help me save her.
Imgur: The magic of the Internet
Imgur: The magic of the Internet


Should I cut more roots? There are a lot of black spots, but they are firm to the touch. I'm afraid it's more damaged than I thought

Thank you so much,
Irene