Ms. Marvel and SS are at two completely different spectrum's of the power scale. Sure, making Ms. Marvel significant was easy. She's not exactly that powerful anymore, and therefore fits on an Earth based team. The Surfer, on the other hand, if forced to participate in Marvel Earth's kinda threats, would inevitably be left jobbing to everybody from Ultron to the effin' Wrecking Crew. I mean, arguably the best run Avengers ever had had the Mighty Thor getting his ass kicked left and right. It just doesnt work. Truth is, one could make the same argument about Supes, MM, and GL with the JLA, but I gotta tell you, they do take on bigger threats than the Avengers usually do. An old weapon created by a fallen pantheon of science Gods the size of a small sun comes to destroy the world, you might need Supes, MM, GL, Angels, God, and six billion superhumans to take it down. Not so much for an invasion by Skrulls in the middle of a war with the Kree, with the fate of Earth in the middle.
But I suppose it could work, but you'd really have to up the ante on threats, and have somebody writing it that can produce something better than ninjas.