Where *should* the ICC profiles be in MacOSX 10.4?

Probably the best place to keep your profiles is in the “System” folder (System/Library/Colorsync/Profiles). That way, they’ll be available to everyone and every ICC aware app on your system.

I would imagine that your profiles alias and recommended alias can be safely deleted. I would not touch those that are in the Adobe application support area.

You could pull them out temporarily and see if that causes any trouble!