I can read people fairly well I think but I sometimes limit myself to just avoiding attacks (which in itself can become predictable and leave me vulnerable instead) instead of baiting and punishing readable moves with the right counters. For example, punishing ledge attacks with a retreating Usmash is a great idea. I usually just shield grab. Those are the kind of ideas I was looking for.Jab -> DSmash is only good for getting a very high % kill, I only mentioned it before because it would've killed them; it's not that good otherwise. It's as reliable as jab -> UTilt; it's not a true combo, but it's not exactly easy to escape either. If you stick to just jabs and jab -> grabs until kill %s, you should be able to catch them off guard with either (as well as jab -> BAir).
I'll watch the video you just posted later; I'll edit this post when I watch it.
EDIT: Done.
Watkins (Ike) vs Memphischains (Sonic)
0:12 - Even though a lot of Sonics like to use spin dash as an attack, you shouldn't use Counter if you're playing your opponent for the first time; Counter should be thrown out when you are sure that your opponent will attack, which comes after understanding their playstyle.
0:19 - More spacing issues; Sonic moves VERY fast on the ground, so be wary when you think of using an aerial; just like he did here, he can simply zip right under you and shieldgrab.
0:37 - If you notice your opponent DI'ing out of your jab combo, you should just finish it rather than rush at them with an aerial; you're more likely to hit them that way.
0:43 - Ike's grab game isn't that good; even though he has BThrow -> dash attack, it only works at certain %s. At lower %s, you should focus on racking up damage, so completing the jab combo is a better option than going for a grab.
0:59 - After the first two jabs, you should've gone for the DTilt then; your opponent DIs very well, so it's very unlikely that he'll be close enough if you continue jabbing.
2:02 - Yay jab -> UTilt.
2:37 - UAir doesn't set up for anything; it's only good for getting kills, so you should save it until they are at high %.
3:18 - If you see your opponent go that high, you should just release the charge right away so you reduce your chance of getting punished; only a stupid opponent will get hit when they're that high, and you really can't take that chance in a tournament match.
General comments: You played well in this match; you were pretty much dominating after your first kill (which explains the lack of comments after the first minute). However, you are still struggling to read your opponent and punish them; for example, your opponent had a tendency to airdodge when he came down onto the stage, but you never baited it and punished it. Your opponent also had the tendency to edgehop an attack to get onto the stage; a retreating USmash could've punished this. Learning how to read your opponent takes practice and a bit of guess work; it might seem hard to consciously think about your opponent while playing, but it is well-worth the effort when you land powerful attacks. Nevertheless, good job with the match and winning.
Makes me realize how sloppy my gameplay gets sometimes, thanks for the tips, I'll aim more outside the box now.