I think the love/hate response is dependent on system configuration and by a massive margin monitor type.
Personally as I work with video and photographic images I _have_ to use an IPS monitor JFGI hehe.
But basically that means far greater image clarity and truer colour/contrast/saturation/shadow depth and to quite honest the "improvements" don't stack up well on this type of monitor; the retouching looks over done and over saturated (nasty instagram filter style) but does look better on a standard monitor which I also use for proofing images.
I think an on off toggle is definitely in order here editing the game sys file is not really fair as, a lot of people won't want to touch itit will look also terrible on low end monitors with low contrast ratios ie and to save typing an essay:
one of the better explainations I've seen posted.
Now I can't possibly show how different they look even with links to pics etc as you honestly have to sit in front of two different monitor types to see it, but it really is quite drastic. You will not really see the difference until you do.
What looks like a well edited picture can look like utter garbage when viewed on an IPS as you can see where the editing has been done (in bad way brush strokes dodging and burning) etc.
So yeah sure fiddle with graphics, but I think certainly make it an option from inside the normal game graphics options.