The thing about Zelda is that, in an approach situation, if she's in the air, it's pretty obvious what she is going to do (This was sort of true in Melee as well but in Melee you weren't forced to spend as much time in the air off a single jump, and could also Lcancel, so you could play with timing a bit more; Zelda sucked for different reasons). For the most part all her other aerials are more useful than they were in Melee: her uair is pretty darn strong if you can land it, pretty much anything is better than her Melee dair, and I'm still working on nair uses. Those are nice and everything but they do nothing for her approach game. Also, it's a fu
cking bi
tch using fair/bair to hit medium to smaller sized characters like Squirtle, MK, even sometimes people the size of GW or Mario. There is hardly any point in trying to hit them with the boot while they are on the ground. Also if you hit someone with the crappy hit of the heel, generally they are out of hitstun before you have finished the move, so that sucks. The heel is awesome to break combos with if you land the sweetspot though.
Of course you could ask "why approach?" and spam Din's Fire until they get close; Zelda's defense seems to be pretty good with the u/d/fsmashes, and Nayru's to some extent, though the lack of hitstun really hurts its usefulness. All her smashes are pretty good, her usmash is actually slightly more powerful than Ganon's, but I think on average it ends up killing later because it tends to get used/decayed more. However if you're in a situation where you can be camped back and aren't leading in %/stock, this is a big problem. I just really see her approach game as very lacking, and this is why I don't think she will get too much past mid tier. Too many people can spam her back or avoid Din's altogether in approach (it's not that hard to just run up to them, shield them, then move forward again), and then you just have to figure out her defensive game, and don't get hit by her up B when she lands. She's kind of vulnerable in the air because you're only really worried about the bair and fair, but if you're below her there's not much she can do besides try to air dodge with her slowass falling speed, or try to up B down onto the stage. Basically if you're ever ahead against Zelda, she will have a hell of a time approaching you if you can force her to do so.
Up B is still vulnerable for a good while after the initial little ribbon hitbox, but her up B with the explodey stuff on landing is great. Fwd B hitbox gets bigger the further you are away from it. It is pretty easy for the opponent to airdodge it if they are close, but if you use it from far away, I've found you can still get them if you play with the timing a bit, and release it late so their airdodge is over and make use of the large hitbox. It's seriously really big, like, PK Flash in Melee big.
As far as I can tell there are very very few true combos with Zelda. Dtilt seems pretty good as it seems you can trip people into another dtilt a fair number of times. It seems like the best way to cheaply rack up damage early on. Sometimes you can get an ftilt or dthrow to bair on someone that doesn't know what they are doing, but I'm fairly certain it's not an actual combo. For throws I really think the best thing to do is throw them as far away from you as possible and resume Din's Fire spam. That and the dtilts are good ways to get your kill moves out of the decay queue. I've started really trying to save my usmashes for when I need to kill, and definitely the better for it, it's a great and relatively easy to land move. You can kill Snake at not much about 100% if it's fresh.
I'm actually seriously considering trying to learn Sheik for lower % so I can approach worth anything, and try to find a way to switch to Zelda to use nondecayed moves to get kills.
