WALL OF TEXT INC......................................................................................!!!!!
I think you remember me, I critique harshly so don't take it the wrong way >.>; You definitely have that fluidity that we wanted you to have the last time you posted. Great movements overall. Now to talk about new improvements you need...
Do you watch your opponent at all? I think you sort of take it all in while your actual focus is on Marth. You really should never look at where Marth is unless you want to check to see if your going to land on the stage or your going to sweetspot(even so you can do this while making sure the opponent doesn't try anything on you). Always watch the opponent. There were many times this seemed apparent. Once on Yoshi's story you edgehogged when:
A. He was high in the air and close enough to the stage that he could (and did) just DI onto the stage.
B. He had is double jump.
What were you thinking? It would have been better to have been on one of the platforms trying to bait out his double jump or airdodge or force him to go for the edge than to let him have an easy way on.
The other main issue is your shffls and attack patters are too automatic. Every shffl was executed practically the same way. While this enables you to l-cancel perfectly it also does:
A. Allows them to just aerial attack you in the middle of your jump if you fair, because rather than intercepting your opponent your trying to fair late in the shffl to perfectly l-cancel it. So you don't react if they actually approach during your attack.
B. Allows them to develop a rhythm of your attacks. Therefore, your own timing is giving them the advantage.
C. You think too far ahead, rather than do a spaced fair then follow it up with a shffl fair combo if you hit them, you fair and automatically dtilt because you think they are going to shield. This results in a missed opportunity if you actually hit them with it. Same thing with watching for them to double jump, you have the range if they get too close you can upair and if they jump you can just fastfall l-cancel out of harms way, if they double jump early you can try to follow it with your own jump and attack them.
Solutions? Watch the opponent! If they jump at you, you need to react and fair or double jump out of harms way, the fast fall and l-cancel timing will be different since now you haven't done it at the peak of the jump, but you should be able to learn to l-cancel this fast enough. It isn't punishable, because you reacted to them JUMPING at you, therefore, you hit them and now you can follow it up. It is also important to develop different timing for executing your aerials. Early nairs, late nairs, pausing, double jumping at different times, etc. All of these will keep your timing varied so that your opponent can not get into a rhythm of when to interrupt your attacks. Eventually you won't be automatic, and everything will still fastfall, l-cancel effectively.
I don't know if this was an accident, but stop backthrowing. Backthrow only really works at 120%+ since it sets them up for a bair or fsmash if they DI incorrectly. Also in the first match the Mario DI'd your forward throw correctly I think everytime, but you still did it. If you were watching him from the throw you would have hopefully seen that he was DIing too far for you to follow it up. Mixing in upthrow (for shffl combo opportunities (go right for it at first, if they double jump you wait for the double jump) and dthrow (fsmash if they DI to avoid fthrow) to make fthrow viable again.
Another point on the actual matchup, you were playing against a Mario. You were too aggressive overall. You have all the range, and not once did you properly (and continually) space fairs and force him to do something to get out of it. You pressured him, but you didn't pressure him to the point where he panicked at all. I'm sure if a few times near the edge you did not approach and just placed fairs and nairs right in front of him you could have forced him to try to jump over you or roll. But often you got too aggressive and went for the grab or just dashdanced away.
On the FD match there were multiple times when you would grab the edge and the Mario would stall off the stage (below the stage sometimes I might add) and you would roll. A ledgedropped to doublejumped bair or ledgehopped bair could have stopped him easily.
The only time dropping off and fairing really works is on fastfallers (since they can't do anything but firefox) and by surprise. Fthrowing near the edge they DI away to avoid the Fsmash you just dash off the stage and fair. Or you wait on the stage crouching like your going to dtilt, then you rush off and fair when you think they won't expect it. Any good player will see a simple run off fair attempt and easily avoid it if they have there double jump and a decent recovery. Almost all good edgeguard attempts are done suddenly (watch m2k or KDJ, probably 2 of the best edgegaurders in the game) or from reading their opponents recovery (seeing a down b stall and jumping out, shining in between Marth's overB, watching opponents recovery patterns then punishing them, etc. It's easier said than done, but when you start understanding recovery patterns you can effectively force your opponent to recover in ways they didn't expect too, enabling better edgegaurd options from yourself.
Your attempts to Fsmash techchase on platforms I have to say were pretty horrible attempts. I'm not sure if you got it once. This may be due to the fact that you don't watch your opponent recover from their techs. I know myself personally I have rather horrible timing. I can read techs perfectly sometimes and still miss attacks (attacking to early/late). You on the majority missed late. I try to see if I'm going to be late and try to do something else (since they expect the fsmash or grab) like dashdancing the grab or spacing a fair and forcing them to roll (particularly effective if they are near the edge).
Work on your timing to hit out of techs. You may be used to fastfalling tech chasing, floaty tech chasing is more situational and mainly done when they DI to platforms. If they land on a platform you should try to be already under the platform, sometimes you tried to wavedash under and fsmash after they landed then recovered. That's pretty readable after you have done it 2 or more times. That Mario wasn't easily fooled he would just wait for it and shield almost everytime. There are better options than fsmashing if you know you already missed the chance. Mix it up and see what you can get to work. I personnally like wavestopping (jumping up to a platform and wavelanding down) to grabbing, pausing then uptilting, spacing aerials, etc. Plenty of options to choose from.
Ok I'm done -_-; As always, there are more options than listed. I just listed the ones I do from personally experience. Your overall movements were much improved and I hope you don't lose it trying to figure everything else out. Loved the dashes from attacks and overall you moved very smoothly. Feel free to question any of my advice or point out if I was wrong or if there were better options.