Luthien
Smash Ace
The point I'm trying to make is, we can't have Zelda's light arrows too much like Pit's. Pit's arrows are magical. They also form magically from his wrist. We also can't have Zelda's light arrows too much like Link's. We can't have them take forever, but we have to have them take a while.Zelda's arrows could possibly be faster. Unlike Link, they aren't really, you know, physical. She just kind of formed them in her hand while pulling the bowstring.
One difference I can think of is he arrows having an aura or curvy trajectory like Mewtwo's standard B. Considering they're pretty much magic, I wouldn't expect them to act like Link's.
The strange thing about Din's Fire is that it isn't truly a projectile. It isn't reflectable nor does it do damage until you ignite it, so it's completely harmless while it follows its path. Perhaps a neat buff they could add is making it damaging or giving it knockback as the fireball travels. Kind of like FLUDD, and you can push the characters with the fireball so they're forced to be in the area when it ignites.
This is because all of Zelda's magical moves (except for up-smash) take a long time to start up; this said, one really fast magical move falls out of place with her character. Too slow, and she'll get punished; too fast, and it will either be too much like Pit's (which, as I've pointed out, makes no sense), or just not make sense with Zelda in general. Finding a middle ground is pretty much impossible.
By the way, that's a kick-*** Din's Fire idea.