I'll do my best to give decent advice:
So far watching the beginning of the yoshi match: too many fsmashes (though they did hit) it's one of your best ko moves, and I don't know the details, but I've heard about this "staling" business so try not to use it too much
You airdodged all his eggs, couldn't you have just walked/rolled closer a few times?
After watching the rest of the match: still too many fsmashes, you should have tried approaching with a couple aerial hammers to mix it up a bit. Your aerial skills were pretty good.
Your shield got way too low at some points, I would have rolldodged some of those eggs, though I'm not experienced fighting Yoshi.
hmm...that's about all. You did pretty good at not getting punished. Maybe try some final cutters, I think if you time it right (which would be difficult) you can hit the flying egg with the tip of the blade on your way down, and hopefully yoshi would be in the middle of shooting another egg and your cutter would hit him. This is just theory though x_x
Vs. Falco: good job crouching the lasers until he got bored at the beginning XD
Try fthrow uair fthrow uair on him, and maybe an fsmash or ftilt at the end, search "gonzo combo" on youtube if you haven't seen it yet.
hmm..don't you hate how incredibly easy it is to powershield final cutter? : ( ... and you also have to hate how you have 2 different "rolls" onto the stage when you're hanging and you press L, Falco killed you because you did the slow one, lame...
-Need more "Hi!" spam when you send falco into the background, please.
-Awesome job turning into a rock between the 2 battlefield platforms, people usually think that you're going to land on one when you do that...and the price Falco paid for his foolishness was death xD
Though you rolled right into his fsmash afterwards...oh well, it happens.
Good job the rest of the fight!