Aight, since you won all of those matches, I'll just critique the one you did the worst on (the first one).
Here we go:
0:07- Maybe a scruple, but walking PS is just as effective as full jumping without leaving yourself in hamrs way by being above Falco, which is bad.
0:09- Get up Fsmash is bad. Don't do it. ESPECIALLY when your opponent is at low percents. There are more problems here than that though: why did you attack when you saw him dash attacking at you? Unless you weren't paying attention...shielding works fine against him in this case since he used it much too early.
If you wanna use a quick attack after getting up I suggest either jab or Dtilt depending on your opponent's percent and distance from you. Jab for closer and Dtilt for farther. You can grab from either, but Dtilt at higher percents can lead to Fair if I'm not mistaken.
0:12- Could've edgehogged and killed him. Naners are cool, but their goal is to help you kill your opponent. Falco off the stage is as good as dead, so unless he's fairly high up, you should go for the kill. Bair stagespike if you're lookin for somethin fun to do.
0:15- I never understood the fascination with that peanut edgeguard. It's weak, you can't follow up, and it's not fast unless charged. It worked a moment ago, so you should know he's going to adapt to your edgeguards. Try a Fair or Ftilt or Dsmash/Fsmash in his landing spot next time.
0:22/23- He tripped. It's a stupid game mechanic, but it looks silly if you don't punish someone for it. Why did you roll? More importantly, why did you Utilt afterwards??? If you're worried about a getup attack, just shield to grab or Dtilt or whatever you want. Most likely someone will roll out of a trip, so be ready to chase.
0:25- Don't roll back just because he's about to attack. Either shield, spotdodge, or attack him first. Standing around doing nothing is almost always your worst option, and here it just made you nervous and miss a chance to hit Rag for doong a silly Dsmash.
0:42- I see what you're trying to do there, but it's too tough. Shield then shield drop and chase, or Fair him right before he does the illusion. The latter is obviously better since it makes even more strain on Falco's already awful recovery.
0:46- Don't wait until your invincibility runs out before you try to return to the stage, Recycle it with repeated edge grabs then attack. You also have your basic getups, don't forget. Make him afraid to play so close to the edge.
0:51- Why did you roll again? Don't give Falco so much room, or he can start to camp you. Not only is that NOT what you want, but it relieves all of the pressure you could've had on him. He even rolled to the edge to make your job easier, but you rolled away too.
1:00- Utilt? Try Dsmash/Fsmash/not Utilt
After this, I see some sloppy sporadic Diddy play. Just because Dash Attack is a great move doesn't mean if you use it you'll win. Have some naners out to pressure with too, or do another quick option after the DA like Usmash or cross up Bair to keep him guessing. Your pressure game was weak here, and good Falco's would simply shieldgrab you or poke you away.
1:17- Falco shouldn't be FJing his lasers to hit you, so don't bother counting on that. Get on even ground with him and nail him in between lasers or hit his head or something.
1:30- I know it's tempting, but if it didn't work the first time, you're better off AD chasing or Fairing.
1:31- Roll got ya punished again.
I will say I liked up to 1:47. You ran away instead of edgeguarding at that point. Too bad, it could've been a 0-death.
1:51- He spotdodged and you...roll? You need to start watching him. Hit him out of his spotdodge instead of running away yourself. DA, grab, maybe forward B would work here well. Also, Dsmash out of the roll was bad since he would obviously go for a grab or shieldgrab at that range. Either go for a grab or do some poke (jab/Dtilt/Utilt maybe).
1:53- When Falco is running at you on the ground he is either going for a shield (usually to grab) or DA/DLX hitcancel. Roll behind, spotdodge, SH AD, SH away naner pull are good options here at varying ranges.
1:59- Bair is bad for edgeguarding against phantasm (lol I said illusion earlier). It's range and priority aren't high enough. Fair is better, even a Nair should trade hits I believe. You could always jump up right after he lands and hit him.
Why do you roll away when he's on the edge so much? The phantasm is not that bad. Stand your ground.
2:19- Finger slip? You could've edgehogged here if you hadn't done that Fair.
2:33- You dash AWAY from him and hope he hits your naner as he has all day to fall to the edge. Stand by the edge and hassle him. Dsmash works. Hugging would've worked here. Naner to falling Fair works.
2:48- He jumped high into the air, and you sat still and watched him fall. Falco's recovery sucks, and a nice Fair would push him very close to the edge. You want that pressure. Make him afraid to slip up so he does. Pressure him and don't stop. Get under him and throw the naner up and follow his DI with a Bair or Fair or maybe you could Nair/Uair for juggles. Glide toss the naner at his landing point to grab to throw him off of the stage to gimp to effin WIN.
2:52- Don't do that. Grab or not Usmash.
Couple big things I'll go over again:
Use more Dtilt and single jab hits for poking and pressure.
Keep moving. Sitting still relieves pressure.
Stay close to the edge when edgeguarding.
Find more naner opportunities/follow up better.
Hope this helps!