My preference would be to use a schottky diode to keep the voltage drop low when the GPIO16 pulls the reset line. There is no significant current so something like a BAT-85. A conventional like a 1N4148 diode should also work OK, but some say this might be marginal.
The NodeMCU does have an on board connection for deep sleep via a resistor but I think this is best ignored.
See https://github.com/universam1/iSpindel/issues/59