I wouldn't say I was overwhelmed with negative feedback but what little I got was always for that variety. I just always got the impression that the untouched backgrounds, warts and all, were what everyone else preferred so there wasn't much room for my takes. Thanks for the good word, ssj.
I don't see the need to make separate art files for the background only view and I think that would just confuse everyone. I never play with the units in view but love having the option to see them. I know many people do play with those views and they look great. Some of Mr. Do's uploads for games like Pac-Man include a ton of views for different versions of the original machine, various fan arts, etc. I love having all these options. If the concern is that they are taking up too much room, then I suggest learning how to work with LAY files and tailoring them to your needs. You can open this in notepad, delete all the views you don't want and delete the element references to those images at the top. Then you can remove all the unwanted images from the zip file.
Just to address a few other points you made:
If the colors of the actual art were darkened, that could vary on a case by case basis. A lot of times I would handle the gray area as a separate element in Photoshop and should have no effect on the rest of the art. DKII has the same grain effect but it's probably less noticeable since the screens are half-size. Same with games like Safebuster. For Balloon Fight, I assume you are referring to the background without the mountains. That one is darker and has a weird color banding effect. I actually didn't touch that one at all since I never use it. I play with the mountain background since that was part of the supplied artwork from Nintendo. Only that crystal screen game came with something like that and I believe it was printed on white cardboard. It actually appears lighter than all the other backgrounds as it should. You can check if Hydef did anything with this in his final versions. I remember a point where I noticed the vertical dual screen games had one screen darker than the other. Not sure if that was intentional from Hydef to create the effect as you would see it in real life. I thought I adjusted them all to better match. It might help to let me know where you downloaded from. What I host on my drive is different from what Hydef is hosting and I'm not sure what Mr. Do uploaded. I'll put a link to my drive below since that's all I can control. I'm not sure what "Tanukichi" is referring to.Game & Watch Artwork (Including Bassmate)