I've been thinking about using Godot in this way recently, would you care to say more about what your experience has been like?
Godot uses a Python-like language instead of Lua, which is good for me. Lots of people groove with Lua, but it gives me the ick.
I did not get very far trying to make 3D or physics-based games with Godot 3. I did not like the 3D interface, and the physics engine was too brittle for e.g. a pinball simulation. Too much tunneling and other inconsistent behavior.
But for 2D applications that are a mixture of text and images, i find it fits the bill quite well.
(For 3D apps and physics, I currently use Unreal Engine 4. Some tunneling, but I know tricks to mitigate that, and I much prefer its 3D interface.)