I do like the concept you have here.
It would be kinda cool to have a 3d viewport instead of a still image in combat, should be possible in godot according to google.
Also if you haven't already try looking into using shaders, so many cool effects. Even if it's just for some simple animation, it'll help keep people engaged in what is arguably the least engaging type of gameplay (Turn-based, atb or no)
I too, would love to see corruption elements and clothing damage in the future. If you do add a 3d viewport, cloth physics and the like would be interesting to see.