Any more time/cost effective product than Optimum no rinse with wax?
 

I started with the original ONR using the Garry Dean one bucket method followed with their spray wax. After a few washes, I switched to the ONR with wax built in to save the time for a separate waxing step. I'm able to wash my car using less than a gallon of water in around an hour, including wheel wells, wheels/tires, door jambs etc. with excellent results.

Are there any other products that others have found to work better than this?

Ultima Waterless Wash concentrate. It blows away ONR in price and look.

If you want to get more serious I'd say a cheap pressure washer and foam cannon. Makes soap 1000x better and you can remove a much greater deal of contaminents with a soap soak and rinse before your actual wash.

For me I use foam cannon pre wash, then hand wash with ONR wash and wax.