Hey Antonio Zalles,
1) I really don't want to implement decimals because it encourages higher scoring, and the scores are high enough as it is. Instead of giving them a 6, you might go 6.3 which is higher than just a 6. If they don't deserve a 7, give them a 6. The average needs to be lower.
2) The filter for creator/fan opinions on the View Opinions section is already planned.
3) The filter for creator/fan for the top 10% list is already implemented. [hands you the "Mr. Observant" award]
Thanks again and have fun!! ^_^