How much does the wheel weigh? What rpm do you intend to achieve? How fast do you want the wheel to reach max rpm?. Are you planning to apply any load onto the wheel? Do you want the wheel to stop suddenly? what is your preference when it comes to torque vs speed?
Also what is the application of your wheel?
For example is it a
-Gear?
-Turntable?
-Tyre?
-Fan?
-Pulley?
-Psychedelic Spiral?
-Cassette tape wheel?
or any other?