ESP32: how to keep a pin high during deep sleep (RTC GPIO pull-ups are too weak)?
It's not clear that making the resistor change you propose will be effective at solving your problem.

The MCP160 requires that the enable input is taken below 20% of Vin to effectively switch the device off. If Vin is (say) 5 volts then 20% is 1.0 volts and, because the ULN2003 is a darlington, it may not reliably switch this low. However assuming it does switch lower than 1 volt then there is still the possibility that my guess about the value of Vbatt of 5 volts doesn't cover the low end of the range. 

For instance if Vbatt is expected to work down to say 2 volts then you can only switch the MCP160 off if the enable pin is taken to less than 0.4 volts. This sounds all to close for my liking and I would recommend you think about the problem a bit more.