I agree. The exterior doors look out of place with the train's texture. However, I don't see an easy solution because you would have to photoshop the exterior doors to achieve the same color of the exterior skin, or get a brand new texture altogether.
The train also needs to have its body reconfigured. Right now, the undercar section is too small and the body too big, so when the train pulls into the station, part of the door lays submerged from the station. Easy fix is to make the undercar section bigger.
Fun idea, is it possible to feature those moving LED screens found on some R143s. It would be cool to see this thing fully animated.