When writing up your powers, there are always a number of things that you need to keep in mind.

All powers must have limits.
No power can be effortless to use, or instantaneous. Unless your power is always on, it will not be instantaneous. Unless your power is a state of being, it is not effortless to use. (And even then, it will likely take effort).

Every power must require some amount of concentration to either use or not use. Even if the use of a power requires minimal use, eventually the character must tire from use of his or her powers. If your character's powers are automatic, they should be on constantly.

Every power must have some range of effect.
Multiple powers should, if possible, be themed with one real power and multiple stunts derived from that power.

If you have as a 'stunt' or affect something which is classifiable as another power entirely, make sure that it is explained as required in the news for that particular power. If a power isn't in this list, be sure to be as detailed as possible in the spirit of the delineations here. Ask a wizard when in doubt.

Powers that are very global in power stunts, such as Darkforce Manipulation, Electromagnetic Field Manipulation, and the like that have multiple power stunts that amount to numerous other powers in effect are quite difficult to get passed. While such grand powers are not impossible to pass, you must remember to impose limitations on your character's powers. Not everyone is a Darkstar, or a Magneto.

The more powerful your character, the more detailed your explanation of the powers must be.

The more powerful the character, the more difficult it is to have that character passed.

Original powers, or powers not already on the MUX have a better chance of being passed than powers an established character has, or a carbon copy of another character's powers.

Certain powers are not strongly encouraged: werecreatures, temporal manipulators, teleporters, dimensional travelers, or characters with multiple unrelated powers.

Note that the list provided here is by no means a full list, nor is it a full list of questions. This section will most likely be regularly updated as new questions arise.