20-30 levels into Alpha Bounce? Yes, that's truly not even scratching the surface. Most planets have 29 levels (you don't need to beat all of them to finish the game but beating all levels of a planet will give you another paddle type), there are 27 planets in the game from what I heard plus the distances between them can get quite large and while you'll likely only take the direct paths to the planets and items there's still MANY other squares in the galaxy map. They advertise something like 16 million levels, they're definitely procedurally generated (though the algorithm gives some pretty nice results) and that would mean the universe map would be something like 2000x2000 squares.
BTW, there's a port of Mega Man 2 for the iPhone. It's got some seriously wonky physics, kinda like the Sonic Genesis game for the GBA.