pic: Team 1325 Custom Wheels

[DampRobot]

Have you thought about how to put tread on the wheel? It looks like riveting is your only option at this point, but you'll have to have some consistent method of drilling their holes. Another mill setup in a vise maybe?

Seconding what others said, these look very heavy. Don't just make the spokes smaller, also conciser pocketing it from the other side. Also, you might want to tap those sprocket mounting holes, so you don't have to it a nut on the other side.