Working on a new project that I want to be very low power while off and powered up with an interrupt on change. I'm planning on having the micro (16LF1847) powered directly by batteries (3 to 3.6 volts) with no voltage regulation. The project will have an LCD (CFAX12864T-TFH), voltage reference for the ADC, voltage divider to monitor battery voltage, and an op-amp (MCP6034). I'm thinking of using an output pin on the micro to power all the peripherals during operation. The current draw would be well within specs but I'm curious if there's anything I'm missing that would be detrimental to the accuracy of the peripherals? Or, would I be better off switching power to the peripherals through a MOSFET from the battery? I want to keep the part count low if possible.

Thanks