You use Final Cutter way too much. Good players will learn to sidestep or simply SHAD above that and punish the ending lag, as it is a fairly slow move. Use it for spacing more than spamming it as a projectile.
Overall, you were much too predictable. Every time you would knock Ganon off the edge you would go for a Kirbycide, and any good opponent can see that coming and instead use upB for a recovery. Also, watch your approaches with predictability. It was always either Final Cutter or going for a grab, and both can be punished easily. Mix it up with Nairs, dash attacks, and empty SHs.
Use shield grabs as opposed to dash grabs, you get the protection from an attack and it's not as laggy when you miss.
On the Fthrow-->Uair combos, a good opponent will get out after the second one, so make sure to do an aerial hammer or Fsmash (depending on if they jump or fast fall, respectively) to end the combo nicely.
Don't use your Fsmash so much, it's your easiest kill move.
You're decent, work some more for sure.
Also, you need to fight better players. You'll get overconfident due to the easiness of your opponents, because they weren't very good.