I guess for the power outages just bypass the stations and:
J: Marcy Ave to Jamaica center
M: Myrtle Av-Bdwy to Metropolitan Av
Z:Suspend
B:Suspend (additional service can be run on the A, C, D, and Q lines)
D:34 St to Norwood
N/Q:Via Whitehall and bypass
Shuttle Buses can be operated throughout Lower Manhattan, ENY, LIC, Downtown Brooklyn, and all the stations with no power
(This most likely won't work, although I honestly think the MTA might do the same thing they did with Sandy, only more expansive here...)