Quick story. I once owned an 1864-L Indian cent that was badly corroded. Without all the corrosion, the cent was in a high grade, maybe XF or so. I decided at some point to see if I could take off the corrosion, and it didn't take long to get it off. Unfortunately, the corrosion had completely engulfed the "L" on the ribbon, so when I got rid of the corrosion, I also got rid of the "L." Of course, it still had a pointed bust, so it was obviously the variety with the designer's initial. Be glad your 1909-S didn't lose its mintmark in the cleaning!
By the way, I do think your coin looks better without all the green on it. However, it's still a dog, IMO.
I did try one last thing and I think that will probably be it for this coin. Thanks to everyone for your suggestions and comments. Just the before and after photos.
It absolutely looks a lot better. I think stopping is a good idea, anymore conservation would probably cause metal loss/ fatigue. I don't think it will grade. But could bring a good price on EBAY.
So, "Karnak" we all could see the pitting on the original green coin. IMO the real question is this: I'm curious if you and others here think the OP improved the coin's eye appeal or not? I for one am very pleased with his results. He may have (?) even used your product.
If someone offered me the original coin or the "new improved" version as a gift, I would choose the "new improved" version. Additionally if it has VerdiCared, hopefully it has some protection for the future.