Dhalsim from Street Fighter is a good defensive character. Granted, he sucks at dealing with pressure.
That is a facet of having a good overall defense. A good defensive character will not only have ways to force approaches and punish mistakes, but they're also marked by their ability to deal with pressure and reset their position to a neutral or advantageous position. Characters with only one of those aspects have a decent defense game; characters with all of them are truly great. For example, Hazama from BlazBlue is extremely good at zoning and forcing approaches with his Ouroboros chains, but once you get in up close he has no ways to relieve pressure other than basic defensive mechanics or having to burn half his meter. He is not, in my mind, a truly great defensive character. Nu on the other hand can zone as well as Hazama with her swords, but also has Act Parser, which is not only a DP but can wallbounce in order to start combos (putting her from a potentially disadvantageous position into an advantageous one). If we want to go with your Street Fighter example, Sagat can zone extremely well with his Tiger Shots but unlike Dhalsim he has Tiger Uppercut, and we all know what kind of an advantageous position you can be when you hit with that (EX. cancel -> Ultra).
To tie it all back in, Zelda's ability to get out of pressure is actually pretty amazing. Now I know you've been going on about her shield grab sucking. And your right, it's still pretty donkey balls. But there's more to relieving pressure out of shield (or out of anywhere for that matter) than just shield grabbing. Now, pardon me for being presumptuous, but you strike me as an avid Brawl player by virtue of you liking BBrawl the best out of the mods. And unlike most people will tell you here, that's fine. There's no problem with that. I was an avid Brawl player myself once upon a time. But as a Brawl player, it also makes sense that you don't value anything more than shield grabs when you're getting pressured, cause really what else do you need when shield stun is so low? Maybe an UpB peppered in there if you're a Metaknight or Marth, but that's about it. So allow me to drop some knowledge.
As others in this thread has mentioned, neutral B is
good. Really good. And not even just OoS. It's extremely useful for breaking combos and is almost as much of a "get out of combo for free" card as Luigi's nair. You can even do it far in advance from when you need to and it'll work due to its long invulnerability time. UpB I haven't tested myself, but in theory it should be very good so long as the hitbox comes out at a decent time. And I've played Ryoko enough times to know that Bair and Fair OoS is a deadly way to relieve pressure. They are deceptively quick and getting hit by one of those will definitely put the aggressor in a disadvantageous position (read: down a stock). Know what else is good for resetting positions? Din' Fire. Yep, I know you've been on a tirade about this, saying that it' much more useful for approaching than defending. And you're right in the sense that Zelda can approach with it - she would have exactly 0 approach game without it. But if you plant a Din's in front of you ahead of time and you get grabbed, what's going to happen? The Dins will explode and either the grab is broken or the opponent cannot follow up...in both cases resetting you from a disadvantageous position to a neutral position.
Being able to break immediate pressure and reset positions is almost as important to good defensive play as being able to zone and throw around projectiles. Zelda has a ton of those options and they should not be neglected or marginalized.
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