Ok, I think I didn't manage to describe precisely what I mean.
Let me give you an example:
That's the kind of tattoo I meant when I said some should really better be covered in order to spare others the view.
That's one of the cases where I think nature would in any case be a good deal better than the painted skin.
(and the guy even has pretty eyes! What a shame he ruined every chance of them getting noticed by a nice girl
A tattoo like this I consider non-offensive because it's well done, esthetically pleasing and unobtrusive: