Not bad. Some things I noticed:
-Way too much rolldodging
-In both matches, you grabbed a little too much. He tended to spotdodge, so doing neutral A jabs would have been better
-Use fthrow->uair at low percentages, and use Dthrow more at higher percentages. Dthrow->utilt SHOULD be escapable at 0%, by Mario at least. You kept using backthrow, but you were pretty unsuccessful at gimping him, so use dthrow instead, it has good damage and good followups.
-Don't be afraid to chase Mario offstage...it's pretty easy to read what he's going to do, and pretty easy to gimp him with Dair. Just be careful not to go so low that you have to recover with Final Cutter....a good Mario will cape that.
-Speaking of cape, try using an aerial in the opposite direction of him every so often, because he may cape it into himself. He used cape a ton when you were near the edge, that would have been a good time.
That's all I can think of right now...overall you were both pretty good, but there is room for improvement for both players :/
You should upload a match of you against a different character too