Quote - ...Does a pic need a 3000 x 3000 texture for a character in the background thats maybe 100 x 100 pixels in the final render ?.....

That's a 9,000,00 by 10,000 sample to image ratio
900/1!!!!!!
resolution overkill?  I think so

A word is not the same with one writer as with another. One tears it from his guts. The other pulls it out of his overcoat pocket
Charles Péguy

 Heat and animosity, contest and conflict, may sharpen the wits, although they rarely do;they never strengthen the understanding, clear the perspicacity, guide the judgment, or improve the heart
Walter Savage Landor

So is that TTFN or TANSTAAFL?