>>41819709Depends on what you consider fun. Honestly, the most fun I had with ORAS was the Secret Bases and the Contests since Pokeblocks had no limit, and I was actually able to play with the team I had dreamed of since Emerald. Though the ending of the Delta Episode was cool too thanks to Deoxys.
However, if you want somewhat more difficult battles, a definitely harder Contest scene, and the Battle Frontier alongside Secret bases, go for Emerald.