It took some time for me to consider upgrading, with the issues I have had in the past with ProTools and El Capitan. Even at ProTools 12.6, I only loaded it on my test (non-production) system as I did not want to impact any production deadlines due to some issue with my software.
At any rate, I have successfully upgraded my ProTools HD system to 12.7, and I no longer have the CoreAudio issues on the Mac with either third party DAWs using the ProTools HD interfaces, or third party audio interfaces in ProTools HD. This is probably the reason why I keep the subscription up to date.
You can look at the details here as to what the upgrade offers.
All I can say is that I am glad I installed it. I installed it shortly after it came out (during the Christmas break), and I have not had any issues since. I’ll keep you posted if I encounter anything.
Cheers!