Hmmm, on the first video, I recommend jabbing to shield punish and other things with something else besides ARing. You got punished a lot more damage than you dealt when were ARing. Because jabbing takes less frames to end and can cancel some hitboxes that are coming at you with it's multi-hit properties compared to AR where Lucario can outrange with a fsmash, it's best to go with jab infinite for shield punishing. AR is only good on enemies to shield punish if the opponent can't attack through it before you can end it so don't use it on people like Lucario or Zelda with long reaching Fsmashes. It just doesn't work.
Don't do falling dairs in a match, their landing lag is terrible. Just simply don't let the go under you so easily so you don't have to resort to those kind of situations where a dair is somewhat tempting. Just NO.
Also, you glide attack too much. Though it is a good attack at times when unpredictable, it's a very bad move if you opponent can predict it and punish since they can just ready a shield and punish or simply walk a few steps making your whole glide attack miss and leave you in their hands. You got punished either before you could get the attack out or after you missed with the attack a lot.
In the first vid, I saw many opportunities where you could have off-stage guarded but you instead shot arrows that usually missed.
Don't use Mirror shield period against an aerial approach. It doesn't cover that high, takes too many frames to drop most of the time, and you have more options with a normal shield.
Second video, you should have rushed to the bottom center of the stage because one of Pit's best games is uairing through platforms while the opponent is trying to gain stage control by beating you there first. Though starting the match with an arrow is good in some cases, this isn't one of them. You want as much stage control when it comes to Norfair. You continued to lack this stage control as you progressed in the match. Arrow less on this stage. Using your aerials give you more damage output. Also, don't run away on Norfair, work on getting to the bottom more.
On :56, that was, I have to be honest, a really stupid idea. Mirror shielding a lava wall may be flashy and all but in a tournament, that kind of crap is what gets you killed. You got aura sphered because of this and then you got knocked into the lava wall for about 30% -_-.
You sometimes glide at bad times. Use your jumps more often. There is a good reason why you have 3 aerial jumps...
Don't spotdodge on Lucario as much. His fsmash and other auro laced smashes have slightly lingering hitboxes. It puts you more of a risk of getting hit. Just don't...
WOW.... 3:10, taunting Pit's longest taunt at like 135% on the second highest platform where he could drop down and fair for a kill. Less flashy crap...
If you think the opponent is going to attack you while you are at the edge of the platform, don't roll dodge into the edge. Rolling across and then trying to punish is a lot safer. You've been punished for this a couple of times in the second video.
Third Video, if you are charging an arrow while they are falling, they probably are going to aerial dodge it.
Lucario's dair goes through your uair. Use it sparingly unless they are above a platform that you are going to uair through.
Again, good glide control but don't abuse glide, it's too predictable when used so much. Punished multiple times again from that.
Again, AR less on those who can Fsmash through it with ease.
Don't ftilt when someone is coming up from the edge. They are more than likely going to do an edge attack when you are that close or do a faster aerial from a ledge hop or ledge drop to second jump.
For the second death, be more cautious about the edge. If they are at a spacing where they can safely attack you and yet have enough space so that you can't uair them from a ledge drop leaving you with only fair or a ledge attack as an option, do a ledge roll and get away from them. Doing a ledge attack or fair leaves you vulnerable to being shielded and punished.
If you are at the upper end of the slope and they are in the middle, use dtilt instead.
Last death was somwhat preventable. There wasn't really a need to spotdodge when he rolled away from you.
Overall, your spacing is very good and you have a good understanding on when to use Pit's faster moves.
Things to improve, less AR on longrange fsmashers, less gliding, less spotdodging (esp, on bad times), and try to offstage guard if the person is almost level witih the platform. Your fairs will do more harm than a bunch of arrows.