Customise an open source game engine for specific purpose

I'm looking to customise an open-source game engine (Godot or Xenko) to fit my specific requirements: 1. User launches custom version of the engine 2. User imports file (FBX/OBJ) 3. User saves file (can be engine specific or custom format) 4. User launches Virtual Reality "viewer" and loads the file to see it in VR From my understanding, the requirement can be broken down into: 1. customise the Godot/Xenko editor to simplify the UI and remove game development related components 2. remove all scripting interfaces 3. create a Virtual Reality "viewer" that can display the saved file in VR This is the first phase of a long-term project. I'd like to find someone to work with using this project as a starting point. When you apply, please include the following: 1. which game engine do you think we should use for this project and why 2. the high-level approach you'll take to work on this requirement 3. if I'm missing any important bit of information