1st match: Be more careful of the new auto-sweetspot mechanics of Brawl; it can really screw you over (as it did in 2 stocks). You should also be more careful about spiking; it's probably easier to just jump out with a FAir for a knockout kill or edgeguard. Also, as comboking said, space yourself between you and your opponent and approach with Quick Draw (side+B); it's an effective spacing tool that lets you either grab or jab immediately after, rather than rolling all the time. You also jab too much; try short-hopped FAirs, but space them so that you hit with the tip of the attack.
2nd match: Ahh, here we go. You were more aggressive in this match, which is a good thing; you clearly played better in this one than in the other one, using more aerials and attempts at mindgamed smash attacks. Still too much rolling, though; use more Quick Draw. You should also try edgehogging the Marth player more; even though they end up on the stage, you can still punish them for it with edgehopped DAirs or FAirs. Again, watch out for auto-sweetspoting; try up+B'ing so that your sword covers the edge and prevents people from grabbing it before you do.
3rd match: Congrats on that FSmash for the first kill; I bet that felt good. After that though, you limited yourself to jabbing and rolling; try doing more to get those kills. Try not to get sloppy while edgeguarding against a Marth; again, watch out for that auto-sweetspot and the initial part of his up+B (which is about as powerful as his untippered-FSmash, by the way).
General comments:
a) Use Quick Draw much more; spacing = key to victory for any character.
b) Don't limit yourself to only attacking with jabs; other commonly used moves in your arsenal should be FAir, BAir, NAir, UTilt, and UAir.
c) Throw more; it'll keep your opponent on their guard and let you position them where you want them.
d) Use Quick Draw (side+B) to recover; it can grab onto the edge. Be wary, however; if your opponent goes out and gets hit by it, you'll hit them but then just fall to your doom and not be able to do anything.