In addition to the Crystal style, if there were also an option for the Sega style, I would vote for it. I have actually never played the SMS version, but the terrain looks visually impressive - the grass, the checkered walls in Sega colors, and the feeling like you are in either a kitchen, a garden, or generally at home. I also grew up with Sega games like Sonic the Hedgehog. One of my levels uses the Sega style, and I had a lot of fun making a level that uses the terrain pieces in a different way from the Sega levels.
If you can unlock the poll and add the Sega style (I'm not sure how the poll system really works), my vote will indeed go for that.