The main problem when people port stages from other games into SRB2 is that they forget what mechanics in the original game make the stage good to begin with. For instance, in a game where the player cannot jump far, an open stage with small holes that block the player works fine, but in SRB2, those holes won't do a thing to stop the player. Just because a stage is fun and works in one game doesn't mean that you can just port it to another game without modifying the design and expect it to be just as fun.
It's almost always better to create an original design, and if you make something based off another map, do just that, "based off" instead of "ported verbatim".