Well, it looks like you're using down-B too much.
Grab more, and stop recovering so close to the stage with spring! You're really predictable and I would probably have spiked you and/or grab gimped you.
Also, stop rolling to the edge so much.
And quit using HA unless you're legitimately punishing me when I can't do anything.
Tilt more, stop staling your smashes. Learn how to space B-air and U-air, because you're using them like a newb.
You might want to stop jumping and using aerials immediately EVERY TIME you pass me with a spindash.
And stop doing Spring > D-air. If I shield the spring (when you're dropping it), all I have to do is run forward and charge a U-smash or F-smash or grab and I've got you.
And for the love of all things fast, stop thinking you're going to be punishing my missed tilts/jabs from across the stage.
1) You can't do that
2) It's predictable and I'll probably spotdodge you.
3) You're better off standing outside my attack range.
Oh, and please learn how to shield grab and followup your throws. You miss so many chances that could have given you control of the match.
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Note:
I just wanted to copy and paste that, because the other thread I posted it in was locked, lol.
On to your problem:
It sounds like you're having issues landing kill moves.
F-smash, D-smash, B-air.
For midweights, keep in mind these %'s for "surefire kills" - 135% for F-smash, 145% for D-smash, 170% for B-air (unless you're off-stage).
Well, first off, those are usually your best choice of attacks if you want to kill at a decent %.
You have to look for openings.
There aren't really such things as "spindash mindgames" - I mean, you can use spindashes to aid and get the effects you want, but when it really comes down to it, you're just using them to force a movement you can punish and land a kill move from.
You'll usually land kill moves when:
1) people are landing (even with autocancelled aerials, and airdodges, they have like 1-2 frames of landing lag)
2) they miss (or you shield) a kill move/grab.
3) they roll/spotdodge
It's nice to take advantage of 1) sometimes - some people hold down to fastfall or spam down+shield to spotdodge, and you can land a hit and catch them with bad DI.
for 2), that's a matter of knowing when/how they'll attack.
3) is my favorite, and it takes advantage of peoples' bad habits and lets you kill earlier. If you notice that when your opponent is at a high %, they start dodging alot more - it buys you so many openings, as long as you read their dodge correctly.
If you run at them, will they spotdodge?
Then run > screech stop / side-B shield cancel (to force a reaction) and charge a F-smash, timed to hit them when they spotdodge.
If you run at them, will they roll backwards? Then run > side-B shield cancel outside their roll range and charge a F-smash.
The side-B cancel is really optional, but the sound/graphics/ 'jitter' can cause your opponent to react.
As your opponents get better, they start doing things like jumping when you approach, or grabbing, etc.
You'll have to adapt accordingly.
