If it went 9 10 9 10 9 instead then it wouldn't need an extra Random icon. I'm working on something now that I'll post to the Roster topic soon.I think for 47 slots (46 playable characters plus the random icon), they would need to do:
1st row: 10 slots
2nd row: 9 slots
3rd row: 10 slots
4th row: 9 slots
5th row: 10 slots
And would have to throw in an extra random icon.