@speendo Hi,
My system is built from a Raspbian Jessie image, with RetroPie (3.8) manually installed, and Kodi installed via RetroPie.
I added a text-mode menu which displays on boot, or after exiting RetroPie, Kodi, or Raspbian Lxde desktop.
I wrote a guide which may help you:
Multipurpose Raspberry Pi – Part 2: Adding a Menu to Access RetroPie, Kodi, and the Raspbian Desktop