ah that's such a good idea!
I've actually implemented the rolling graphic somewhat for the purpose of time consistency although I was having the opposite problem. it always performs the loop so fast I had to add the "rolling..." to obscure the result because if you got the same number again there was no way to tell if you had even rolled!
I imagine this may be because the numbers are so small its unlikely to loop for too long and the Gameboys an actual beast of a machine! So the time differential from start to finish is currently not really perceivable but the potential is certainly there.
Honestly, really smart thinking that I'm eager to implement!