WPM isn't entirely wrong to call Double Crisis kind of gimmicky. All we've seen, and are likely to see, are Aqua/Magma cards. There's nothing wrong with that but it does limit the uses for all of these cards unless one is willing to build a deck based just around Aqua and/or just based around Magma.
That being said Magma Great Ball is pretty good. The one thing I can't quiet tell, does it search for fire energy or fighting energy because either way that's a small limitation compared to the Pokemon that are part of Team Magma. I personally think it should give an option of fire OR fighting, but whatev. If Aqua ball does the same thing it will be pretty neat.