Salut Florian,
Thanks, just wanted to be sure. Sure I could, but to be honest, I’ve so much things in the pipe that I need to avoid to burn my brain, but I’m sure you know that as I 
I digged into the m5 code to see and discovered is was not a oled one likes on ttgo, may be faster to buy a m5 board on my side 
BTW, I tested on heltec board, LoRa is same pinout than ttgo (lucky we are) I started to add this in config_LORA.h
include until I discovered it’s the same.
Anyway just to go fast if you’re interested (sorry I could PR but I’m tired, got too much time spend trying to have my repos synced from master each time I fork for just a little change)
Here are the platformio.ini addition for heltec board (also added BLE but I let you remove this to be compliant with existing code) 
default_envs = heltec_wifi_lora_32
[env:heltec_wifi_lora_32]
# See products version pinout differences here (also for ttgo)
# https://www.thethingsnetwork.org/forum/t/big-esp32-sx127x-topic-part-3/18436
platform = ${com.esp32_platform}
board = heltec_wifi_lora_32
lib_deps =
${com-esp.lib_deps}
${libraries.ble}
${libraries.lora}
build_flags =
${com-esp.build_flags}
'-DZgatewayLORA="LORA"'
'-DZgatewayBT="BT"'
'-DGateway_Name="OpenMQTTGateway_ESP32_BLE_LORA"'
'-DLED_RECEIVE=25'
'-DTimeLedON=0.1'
'-DLED_RECEIVE_ON=1'
Noe also LED for TTGO board is GPIO22 reversed 
'-DLED_RECEIVE=22'
'-DTimeLedON=0.1'
'-DLED_RECEIVE_ON=0'
Really nice platform you made, congrats, love French touch