Imagine a scenario where the server crashes. It already takes about 90 seconds to get booted up. If you need to log in through ARD, change resolutions, and adjust setting, you could add on as much as an extra 2 minutes.

Incidentally though, if you still want to run 1280x1024x6 or 1024x768x6 consider writing a scrip which automatically changes the screen resolutions. The script could work the same as what you are attempting to do now and the script can be executed through an automator action.

When I've done 2 TH2G in the past, this is exactly how I've done it.