And 1 more, is Dtilt just a bad Dsmash?
First of all, edit your posts please <_<
Dtilt has a meteor smash, meaning if you can space it, you can shock and style on people with it [it's not actually practical on anyone besides maybe Falcon and Ganondorf though]. Onstage it's amazing because it has reduced knockback compared to dsmash or non-meteor dtilt [since it's launching them off the ground - it's a game mechanic thing] and this makes it way better for getting a dair [at that ~120% range if I'm not mistaken], since it also has longer hitstun [I can go into technical details, but again, it's how meteor smashes on grounded people work - kinda like how Falcon's stomp sometimes leaves enough time for a knee even after a missed L-cancel].
Dtilt is also safer on shield than dsmash [I believe dsmash is -25/-14 on shield, while dtilt is always -11 - from the frame data thread]. This is primarily due to less endlag, which is also why dtilt is better for setting up that dair.
However, dsmash is faster [by 5 frames, which means dsmash is about 50% faster], so dtilt is much, MUCH easier to land, especially out of a crouch cancel.
I use dtilt during shield pressure strings sometimes, and also on a hard read or when I think I see an opportunity [perhaps I just landed a bomb or something]. If you treat dtilt as just a bad dsmash, you'll be...fine... but you'll miss out on some edgeguarding stuff [dtilt -> fair is great if you miss the meteor, and if you hit the meteor on most characters you can at least jab to then hit them away and then do whatever] and you probably won't get dsmash dair often, so you'll have to dsmash uair or dsmash nair/maybe fair and edgeguard more.
Another general question I have, is what are my best ledge options (recovering). I tend to use Fair too much, but when they catch on to that I'm sure it will get punished.
Fair, nair, uair, dair from the ledge are all possible/good [even bair from the ledge has its uses], and you should be able to do each of them. Uair is awesome for covering Falcon recovering just above you, hitting a spacie side+b when they're going above you and you're on the ledge, or if you think you've read someone coming from directly above [this is risky], dair is also good vs Falcon and is good for hitting Sheik when she uses Vanish onstage. Don't dair onstage as a ledge option if they're edgeguarding you please.
However, you can't only attack onstage. Link has an invincible ledgedash of 9 frames [less than the best, but none too shabby] and a true haxdash [fully invincible but requires frame perfection] which is useful for getting hookshot back. I also tend to think Link's roll provides an acceptable mixup, and I love both Link's under and over 100% getup attacks [the over 100% one reachs extremely far (though I don't think far enough to poke Marth charging fsmash)]. The important thing is to mix it up, BUT I'd say your options are:
- Invincible ledgedash [haxdash before to bait out something if you can]
- Invincible aerial onstage
- Aerial onstage/empty double jump onstage [aerials onstage should be invincible on startup most of the time, but if you see your opponent do something leaving them in lag, you can just punish right away]
- Ledgedash [you should try to be invincible, but if you're not constantly planking you'll be predictable, and there's also the fact that if you start planking and only do ledgedash out of planks they'll know... so mixups are important... frankly I'd try implementing always planking or plank into different options, but ledgedash is good even if you aren't invincible all the way, since it leaves you with your jump]
- Over 100% getup attack [under is less good but ok]
- Roll
- Neutral getup
-Ledgehop [aka tournament winner]
Note that from ledgedashs you should often [but not always] do some action afterwards, like jab, dsmash, spin attack [ledge dash invincible-startup spin attack is possible] [this one is risky don't actually do it], grab, nair, or even a roll to center stage or a spotdodge [don't do these too much]. These options are sort of arranged in order of descending usefulness [so I think invincible ledgedash is generally best], but mixups are important - if you always ledgedash, then that invincible fair can take them by surprise.
I'll let Lootic answer other stuff or answer it later, since this isn't exactly a small amount of stuff for you to read in one post.