Edit: Thanks, watched them.
You have a solid Marth for the most part. A few things you might want to try out are:
Your friend missed alot of techs when you dthrew or fthrew him quickly, and since Falco can be gimped easily if you get him off the edge you could have exploited that a little more.
Not sure how serious you were playing these but you obviously didn't chaingrab which is normally good to do against Falcos.
Generally after 50% you can't uptilt Falco or Fox if they DI fully. You can Fsmash tipper if they DI away from you though. If the don't DI you can either do the turn around tipper Fsmash which you did a bit or you can do shffl upairs or a tipped fair to a tipper fsmash if you do it right.
You moved well against his lasers, but try not to shield so early. If you can get better at shielding right at the moment you will throw off there l-canceling alot better and maybe get a powershield or two in there.
Shielding a laser and immediately jumping to fair when the shield stun is over can net you a few hits as well. Your friend was very aggressive and you could have downB'd (counter) his lasers every once and a while to throw him off.
Overall I liked your movements, may have been a little flashy but it was fun to watch.
