I'm a relatively new Zelda/Sheik player (main Peach), but I think Zelda is an awesome punisher -- she's all about finding openings and killing in very few hits. If your opponent plays too defensively/forces you to approach, you either play your hand with some mind games or you change to Sheik and combo the camp out of them. I don't think Zelda was designed to be a main-able character, instead meant to be used in conjunction with Sheik -- situationally.
Depending on how I feel about whom I'm up against, I'll hold down A (or not) before a match. lol If I'm at a high percentage, Sheik just doesn't die as easily after being hit; and I'll change to at least get a few critical hits in.
It always feels so cool, though, to transform back into Zelda to recover from where Sheik wouldn't be able to and just barely sweet-spot the edge. So in that situation, what can you do with Zelda? You can recover with a quick f-air from the ledge, and maybe it won't be a baby hit; you can drop down a little and use a u-air, fast-fall and sweet-spot back; or you can drop down, transform into Sheik again and recover however you like. I know that I'll occasionally catch Marth off guard by f-air recovering with Zelda, and he's usually right at the tip of my foot. Gotta change it up, though.
You'll probably know right off the bat if someone doesn't have a lot of experience playing against Zelda. When I fought my first Zelda as a n00b Peach, all she did was run away from me in Hyrule, back-kick me and kill me at 80%. Pretty much, they'll run right into your kicks because they have no idea what's going on. They won't know where you'll land with your Farore's Wind, etc.
Otherwise, against good players, it's probably best to use her when you're at a low percentage and they're mid-high; to change the pace for mind-games; or to go for a surprise F/U-smash KO.
I like to edge-guard with Zelda if I see that my opponent is coming from above, since she can double-jump out, position herself, f/b-air, and still make it back safely with Farore's Wind. lol It's also hilarious to actually get her spike to work.
Anyway, I'm not the best Zelda player but I have a good hit-percentage.
This is my favorite Zelda video.
My approach to Zelda is to watch my opponent more than myself. Work the camera-angles by turning around, spinning in place, or dash dancing. Control the pace of the match and catch your opponent off-guard. Also, I try always to land on my feet (smash left/right at the axis of your fall parabola) -- it just keeps you from looking sloppy.
Din's Flame -- As you may have seen in the video is very simple to use in the right situations. It works best after a b-throw (especially), a f-air, or a f-smash. I find that people fall in a very predictable manner because of the game's physic's engine. When they're falling and then double-jumping back toward the ledge, or even just landing on the floor, they fall in a very natural looking parabola. If you start the Din's Flame immediately after your opponent is launched, it'll be just slow enough to catch them after their next crucial move. Even if your opponent is slightly above you, keep in mind that they're falling and that you're basically trying to pinpoint the moment when they will land on your explosion. Eventually they'll grow some balls and start fast-falling when they figure out you're watching them, but then all you have to do is explode it in their face instead of under their feet. Depending on the angle that they hit it, that is the direction they will go. I like catching them from below because it bounces them up and leaves them open for that last f-air.
U-Air -- I like this move a lot. I only use it with the c-stick, and immediately fast-fall after the strike. The timing is tricky, since you have to wait a beat. But, I find that if you fast-fall immediately after the strike that makes the hit, it's tremendously easier to intuitively learn the timing. Instead of waiting until the peak of your ascent before c-sticking up*, wait until just before the peak -- you'll know you did it right because Zelda's arm and head will be covered by the explosion a little bit as opposed to the explosion being somewhere above her head. The fire is all for show; it doesn't do anything -- Zelda needs to touch the opponent.
* (It just helps to eliminate that annoying double jump lag/air-halt -- if you're jumping and holding up at the same time, good luck hitting anyone who knows how to fall side-ways.)
Tilt Game -- This may just be me, but I love her forward, up, and diagonal tilts... With the hand waving and the magic sparkles. It's why I started playing Zelda. It just looks so hard-core to swipe at the ground, even if they do roll away and it misses.
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Usually, I'm sure the f-smash is the better option... But if you position yourself so that you get them right at the tip, they'll fly straight up. The range is shorter than the f-smash, tho, and she leans forward instead of back so she's more vulnerable buuut... It's cool, and a better set-up at certain percentages than f-smash :embarrass Dash attack, wave dash forward, and catch them in a bounce with a quick swipe followed by a f-air or u-air(!), depending on which direction they go.
That's all I got that I haven't read on these boards yet. Hope it was helpful to someone. Oh! In conclusion, Zelda has a limited skill-set so you have to be creative if you don't want to be boring. Still, it's silly to complain because all you have to do is press down-b for a whole new one.
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