Alright my advice in particular is to be very careful with Sonic's down aerial. I noticed you tend to use that a lot, it leaves Sonic victimized to almost any strong up aerial by an opponent, like Link's sword. I try to only use the spring for recovery and preventing a foe from getting back on stage. It's not much but sometimes it works well. Also try not to get too grab happy. You are a lot better than I am in nailing grabs but be careful to not do it too much or you leave Sonic open to an easy hit, such as a homing attack. Overall though I loved your style especially the up throw and up aerial for a finish, that's vintage Sonic. And I know you're only going to get better, just be patient at times and make the opponent think more than he/she should.
