Psychology is Important
The interpretation of the psyche is very important and can never be too thorough. This is a text-based roleplaying game. The be-all-end-all of the game is not to beat each other up but to explore the characters and develop them.

Specific Power Levels
We need to know how strong, what ranges, max and min, of every power, be it physical, mental, magic, what have you. For example, we want to see that Colossus can lift 80 tons, not that he has super strength. Whenever possible, assign some sort of tonnage or comparison to a value. Also be explicit about weaknesses and limitations! Review 'news powers' for helpful guidelines for constructing a power set and 'news skills' for skill sets.