Character preferences?
Mine
Link- Bread and butter, somewhat slow, but plenty of projectiles to stun opponents then spin attack to knock around. Most of the time it's boomerang>>dash strike> spin attack.
Bow for sniping or when a foe gets out of a jump and close to the stage to where they can't block unless they wavedash to the stage then you could boomerang>>spin attack
Hookshot- extends slightly out of sword range good for suprising opponents especially if they have longer reach(read: Marth and possibly Roy) Marth's blade is slightly longer than Links I don't know about Roy's though.
Hookshot + up>> spin attack, hookshot+ down>> spin attack
or if you want to be a little fancy
hookshot+ down>> A+down(slices down on both sides) opponent should be flying at this time then>> Up+ A until he's K.O.ed
Of course the opponent needs to have some damage on his belt and pending weight takes more Up+ A to pull off, which is what the first two Hookshot combos are for
Boomerang- good reach and great starter for combos, it stuns very well regardless of damage and only gets better as your opponent takes damage. It can be deflected however so I advise using it only at close(outside of sword range) to medium range.
Conversely if your opponent is coming up a ledge
Throw boomerang as far as possible, enemy comes up and you engage and the boomerang comes back and stuns, just in case the enemy gets you in a bind or is starting their own combo/knockout
Young Link
Used for enemies that are fast since fighting them on link= pain, only problem is that spin attack isn't a knockout blow anymore so I rely on up+A and down+A in the air. His spin attack is good for recovery and getting around fast opponents.
Most of the techniques for Link are good for his younger version only that his boomerang has shorter range which isn't that big of a deal, however his hookshot is shorter, bombs...are bombs still useless. The bow is nice because it's weaker but you see little flames=3
Sheik
I don't use him as much as i used to, but he's the better one that I'm good with for speed and juggling, needles are a bit meh and the recovery is the same as boomerang but not worth it since the stun isn't as strong.
I've never used the whip in the air(supposedly it makes you float if you twirl it fast enough, never seen it though), only used it to stop slow, strong projectiles.
Sheik is really for situations I'm not really serious or worried about losing
Ganondorf
Mostly fun here, most of his attacks are all knockout blows except for that retarded leg charge move that leaves him open, special moves are good for closing in since he's rather slow. No projectiles which makes me a sad panda but still good to use
Worst enemies: Marth(good ones),Fox,Luigi, Cpt. Falcon(good ones), and Kirby though I'm probrably forgetting a few
EDIT: Giga Bowser is a bitch, I hate fighting the hands that is all