I will try to recreate the bug later. With game space, I would say that the width is good, but the height felt really limiting. I would suggest looking at how one or two more height would play like.
Thinking some more about it, the scoring of 2 through 6 is also a bit off. Getting six sixes is exponentially more difficult, but per die the score is equal. Now going only for low numbers gives the same score as going for high numbers while being far easier.