Evenin', brother. You fought valiantly. ^^
I'm no pro, never was, never will be...
But, if I may, I've been playing some serious Samus this past week, and got a lot of good pointers from other people on the boards...
And it would be my pleasure to offer a fellow Samus player some advice/my own thoughts on how to play her.
-Disclaimer, I'm no pro.-
Alright... First of all, you make good use of your forward tilt. Don't stop doin' that. ^^ Forward tilt is your bread and butter. Nice use of the throw+up Ice smash. I learned something new today. :D
Okay, now for a few tips.
First off, I understand if you prefer ice Samus over fire, but don't start a match out by switching. Most players will want to rush you, so as soon as the match starts, pop that super missile! Missiles, also Samus' bread and butter, try to pressure medium/long range by short hopping and popping a missile right before you land. If you time it right, it'll cancel out the animation and you can proceed to do something else right after. Works for both missiles. Try to jump backwards while facing the opponent and doing this trick to give you some breathing room. (short hop)
Always try to have a full charge, but don't charge when it's not safe. If you see someone recovering back to the stage and you have a clean shot, TAKE THE SHOT! ^^ NO MERCY >:D
Defensive game... Okay. If someone's on you like butter on toast, pop that down b. Bombs. Always be bombing. Abb. Especially if your opponent is dumb. Let them run right into your bomb field. Works good if people are chasing you in the air, but keep in mind it's not always your best option.
Samus' short hop is terrible, btw. So it's gonna be hard to be aerially aggressive with her. So you must learn to Zone! Keep your opponent right were you want them, with missiles/bombs. But, if you need a quick and ranged option, you can short hop, and near the full height of the short hop, air dodge left/right and hold the shield button, during the animation, press the A button for a nasty surprise... ^^ Using this technique you can attack quickly while being low to the ground. Experiment with it! (It's her grapple beam aerial, by the way.)
Recovery... Alright, use her Screw Attack when your right below the ledge, but make sure you stall long enough that when you use it, you just catch the ledge (but keep in mind, most everything in smash is situational, so the more you play the more you learn on what to do when) and if you're anywhere but right under the ledge, hold up, press the shield button for an air dodge up, hold it, and press a. Yes, I seen you use her tether recover during the matches, but it looked like you used the pre set button to perform this, which doesn't allow you to use your air dodge to gain extra height. Keep in mind though, only air dodge up if you NEED the height. Just practice on several stages to find the range of all your recoveries.
ALSO for recover over long distances, and for stalling near the ledge, you can bomb jump. I did see you use your bombs to make it back, but you can also bounce off of them in midair to gain some height. USE THIS TO YOUR ADVANTAGE! ^^ Just practice. As soon as you lay a bomb in mid air, lay another one, then bounce off the first one. (If that makes sense?) It works.
Hmm... what else...
Don't be afraid to go in for the kill. If someone is near/off the ledge, stop zoning. KILL THAT SOB!!! Down aerial, neutral aerial, back aerial, ALL SORTS! ALL SORTS OF OPTIONS
Use your boost ball move to catch them off guard, if you roll past them, while still in morph ball, roll back a bit and down tilt them as their hitstun ends for a good bit of damage. (fire mode)
Also, try mixing up her modes according to what you need during the match. Fire is great to start off with, while ice is great for keeping them offstage. (In my experiences, other peoples mileage may vary.) Fire mode also has two very strong moves in the forms of her forward smash and down tilt. Try to land her fire mode forward smash at the tip, where the fireball forms for great knockback.
Don't be afraid to use her fire mode up smash either. It's great for attacking people safely underneath a platform and is a decent combo filler (with pretty good kill potential at around 100-130%)
Underneath her armor... Samus is a delicate lady. You must learn balance, child. And balance will teach you to be delicate. Make every move deliberate. And make your opponent hate you even more with each move you make. Pressure with your missiles. Aerial chase with back airs.
But be delicate. Be gentle.
But never... never hold back.