My broken, inop, crystal ball predicts that these will be kept for sure

DFW
MIA
PHX
ORD
PHL

Others, I don't know. I say "above kept" because too much existing investment and infrastructure (and the bottom line, customer have become conditioned to them....) at these hubs. Harder to fold up the tent and pack it away than keep it and exploit its advantages.

What I see is more international expansion/coverage versus domestic. Maybe some more PHX to Hawaii, Vegas to Hawaii (not technically international but....), PHX to additional Mexico cities, etc stuff