I don't really know if you're looking for advice on this one since it was quicly done x)
The most visible flaw was the eye transition at 10 seconds which is basicly just a hole in his eye so it's weird x)
The thing is to make us believe the image you're putting in this eye is what he is actually seeing so it needs to be like "under" the surface of the eye (therfore we need a superposition and/or transparacy of the original image on the masked image and the incrusted one to give a little texture of glass)
I don't know if my explanation is clear but you really need to make those transition more credible and you should be fine
Well, thanks for sharing and HBD RLD xD