I think items, especially high end should be painted according to any prototype out there or paint chip, balanced to normal daylight. And put that notice in the catalog, and on the net version.
Even something painted the right colors ballanced for daylight is going to look different under a light nallanced for something else.
This way, Lionel, or any importer can cut down problems from the get go.
Now, if Lionel wants to produce liveries never done, they can go for it....