1. Seems pointless tbh. Javascript is not that hard, and adding a new Language support would be a massive undertaking for virtually 0 benefit.
2. Maybe interesting, but I'm not sure if the current renderer as is is set up to support this? Construct is still first and foremost a 2D Engine.
3. As noted above, Construct is a 2D Engine. The 3D features are not meant to go much further than they do right now. There's plenty of 3D engines for you to pick from. Godot comes to mind, though Godot never clicked with me. I really really really like the event system in Construct, and I really understand the wish for Construct 3D, but it's not gonna happen. Construct is already being hardcarried by Ashley (and Diego) but that's just 2 people. There are simply no resources to make a 3D Version.