try full jumping and using bair on the way up. you should be able to barely hit their heads, and easily float away without fear of retaliation, or alternatively, you could hit them on the way down. full jump bairs are also really good if you can predict jumps. at early percents they will combo into a uair on the way down, and those lead to rests. good times.
dair to usmash is a semi reliable killer around 100% for peach, and probably a bit more for samus. don't use this combo when they are at low percents; they will just hit you back during the lag of the dair (there's still lag even if lcanceled), whereas if they are at higher percents they will be carried slightly into the air. well, samus you should usually have killed earlier than that by messing her up off the ledge. it's a bit harder against a skilled peach.
vs samus
shield a lot/attack from above
just float over missles and float to run away
know that fair goes through missiles, and a retreating one from above is a good way to hit him
if samus shields your aerials, instead of drifting back, lcancel into a grab or an attack or something, since samus can't shield grab well, and up b out of shield is *** and can be avoided with good spacing/prediction
vs peach
think -- don't just spam bairs, predict and hit
attack from above and aim for head
uair for early ko's
fsmash for early ko's, but don't spam them - use them when you really think you can land it
use bair/fair/occasional pound as your main attacks
make sure you land every attack outside of her dsmash range
like if you want to use fair, make sure you always drift away after hitting/missing
