The remakes are always harder than the originals. In the game I'm playing now, I only fought the E-4 once (and just barely won) and I'm still afraid to battle them again with my team of Lv70's because they're that strong!
And then there's Steven...
AND you have to fight both evil teams instead of one, and all seven frontier brains (twice), and everyone's stronger than before.
It's definitely harder.
I think it's more fun that way.