Hi, the current OSPi enclosure has no space instead to include a display — adding a display will make it significantly taller, and wiring it / assembling it with the rest of the circuit is complicated / not elegant.
There was a pull request in the github repository from a while back:
https://github.com/OpenSprinkler/OpenSprinkler-Firmware/pull/8
and adds I2C LCD. I’ve not tried it myself and it’s only compatible with the version of firmware at that point.
There is plan to unify the hardware of OS 3.0 with OSPi, in that OSPi will be connected to OS 3.0 (minus the ESP8266 chip inside) via a 4-pin cable, and since most components (including OLED) on the OS 3.0 circuit boards are I2C already, it allows OSPi to talk to and control all components through I2C. This way, OSPi will use the same hardware as OS 3.0, except it uses RPi as brain instead of ESP8266.