I like how crisp and concise your Meta Knight is (I actually watched/studied some of your old vs. Pierce videos when I first started to study the MU).
Just some quick notes:
It isn't a good idea to glide into Marth's immediate attacking zone (no adjustment required for Marth), especially when he uses his second jump to come after you -- Marth players almost universally wait when they've used their double jump and you aren't within their range. When Marth has committed himself like that and he can't drift back to the stage without grabbing the ledge, I usually wait a bit and Neutral B just over Marth's head back to the stage (this is especially good when I'm ~100% and even better when Marth is 100%+).
This allows MK to make it back to the stage without being killed. If you space it properly, Marth can't Down-B or -- if Down-B does get hit by Neutral B -- the counter will not hit you, Up-B's knock back will very sour, etc. If you are high up, Marth can still punish you. Fortunately, you will be much closer to the stage (less likely to kill), your jumps will be renewed, and his kill options will probably be from a grab. This is as opposed to you dying ~100% from a Uair/Fair/etc. You used Up-B instead of this on the second match and the main reason that you weren't punished by it was because of Pierce whiffed the punish. If you used Neutral B, you would have been able to auto cancel and still had mix-ups if he chased you (likely unnecessary since you should have returned to a suitable position before he could enter your zone).
This is mostly just a preference, but you seemed to go for the gimp a bit too much. The risk/reward is good since you risked some damage and full stage control vs. his remaining stock, but ledge trapping was much more consistent in dealing damage and then returning him to a bad (sometimes more easily gimped) position. I do like how you were switching up on that aspect -- that's a good idea.
When Pierce was reverse Up-Bing toward the end of both matches, you could have ledge dropped>jump>Daired to end his stock. You don't seem to handle pressure off of the stage well in general and some of your pressure habits reminded me of Lucario haha. Don't be afraid to glide low against Marth (if he's coming after you, it's extremely televised) and you should be able to recover to the other side of the stage if you want to (you'll be on the ledge, but Marth doesn't have many options to ledge guard against it). ~1:47 on Game 1 you were Uairing Marth to finish a Uair chain, whiffed, and were punished for a decent amount for it. To prevent that, try fast-falling your Uair chain finishers. Even if you're wanting to react to his air dodge or lack thereof, you can still punish it with your remaining jump/Up-B.
What do? I really need help with the Ditto.
