Use whatever side you like better! As already mentioned solids have no "right" sides, a lot of batiks I like better from the back -- but truthfully once they are off the bolt I don't really know which side is "right".
If a fabric close but not quite right, tea dye or bleach or I've been known to draw lines on tone-on-tone prints with a sharpy pen. Now, we don't know if those fabrics will hold up 100 years from now or not, but I'm making them for me/this generation.
My best "wrong" side story is a Storm at Sea I made. I don't know how many times I handled each block but somehow I missed realizing that one of the larger pieces was inside out until after it was hanging at a show. No one else ever commented on that piece...