Yeah. While I don't actually have ToS, I know exactly what you mean. It pretty much applies to any kind of RPG, though sepecially 3D ones.
Smash Bros seems like it would benefit more than any other kind of fighter from danmaku to me. For example, like how there's two shot buttons in IaMP/SWR, most characters would have two types of projectiles - the normal danmaku bullets, which would be similar to Fox's gun in that they do not stun the enemy, and deal minor damage, and then the actually powered projectiles.
It'd change the game in that two types of players, and so two types of characters would emerge for it - those who focus on avoiding the danmaku to keep their damage low, as it could add up easily, and those who'd smash straight through, hoping to deliver a blow that would even things up.
At least, that's how implementing danmaku into SSB seems to me.