I'm using Emerald because the goal of my rom hack is to "update" emerald specifically. There is a lot of content exclusive to emerald that R/S just don't have. I don't want to omit any of emeralds content. I just want to update its sprites to newer, fresher looking ones, and also gradually work towards updating the visuals as a whole. To have similar visuals as the Flora Sky emerald hack, and similar sprites as black/white gen. It will take a very long time though considering to my surprise nobody has perfectly resized all pokemon from gens 1-3 from the black/white series. I'v only managed to find few pokemon converted, and some of them people didn't even do the shinies.