A couple new cheat codes come to mind...

knoppix xquery [IP] *query an outside X-server rather than from CD
knoppix non-fb *no framebuffer startup (i know it's been mentioned)
knoppix iso=[iso location] *such as iso=/dev/hda1/temp/knoppix.iso

I know that last one is a bit obscure, but it would allow for burning just the isolinux stuff you've made and boot off an iso sitting on the hdd, speeding development.

It would also be great if kappfind or something of that sort works correctly in the chrooted environment. I'm personally having problems updating the menu system, and keeping changes such as kicker configurations while remastering, though i'm sure that that's due to my own ignorance.
As someone else noted, after knx-hdinstall netcardconfig is needed, that will need to be fixed.

On a side note about your project, do you think you could provide scripts, examples or a good howto on the splash stuff, I didn't quite "get it" from your brief howto in the original knoppixkde thread.