I would make the following changes to you list:

Drive the vehicle _hard_ for >40 minute on the way to the SMOG test. I don't
know about letting it idle.

A new catalytic converter will definitely help . I would wait until the
vehicle fails the first smog test before investing in one.

I always make sure the air filter is new (or clean i.e. K&N).

I always change the oil  _minutes_ before taking the vehicle to be tested.

Tune-up parts, like plug and wires, cap, rotor,  would help.

> http://www.blueskycleanair.com
>
>
> What I think:
>   - O2 sensor must be hot, but usually gets to proper operating temp
> in under 2 minutes
>   - cat must be hot to eat the pollutants.  Drive 20 minutes on the
> freeway and idle your van while you're waiting for the testing
>   - a new cat might help
>    - changing oil might help