Alright. The following comments are based on WAAA Tournament vs. Yoshi 1, 2 and 3.
1. I would consider that match as being a practice run of sorts. Yoshi killed himself three times. There's not much to say, but you grab a lotttt. I've never been in or watched a tournament, so maybe you just wanted to play it safe? Either way, lots of grabbing. I felt more damage could have been done with more smashes/locks.
2. Again, lots and lots of grabbing. A couple of pointless suicides that could have been avoided by waiting a bit before vanishing. I noticed a lot of the time you were hitting him left, then right, then left, then right, and trying to KO once he reached high dmg with strong moves. I think you could have tried to take advantage of Yoshi's sub-par recovery by positioning yourself to try to keep him off the side. Since he is somewhat strong, you needed to KO him at low percentages by edge-guarding, which is something I know you can do very well.
3. Yay! I think you started taking some risks, and they really paid off, especially as the match progressed. There was less grabbing, Zelda made an appearance, and you pulled off some smooth f-tilt locks! You didn't follow your moves up for the first half or so as much as you could have, but that started improving as you came towards your last stock.
The last minute of Vid 3 was definitely the best out of all those matches. You jumped around more, making you harder to hit, smashed more, fast falled more, attacked and hit more...
Basically, from all three vids, I think I could sum it up with:
1. Grabbing less, or following up throws (granted, you do that often). You know that he air-dodged after most throws, so you could have trapped him by just jumping and faking it.
2. More follow ups. i.e., continually pressuring your opponent off the side.
Everything else was just minor details. I think it came down to you warming up. I assume that was your first match of the tourney.
Paralyzer + Forward-B will give those little buggers hell.