Alright, here's a wall of Sonic feedback.
WHILE-WRITING-EDIT: Sorry Gold, there's gonna be some rambling.
Sonic still has plenty of approach options - you have normal movement just like everyone else [except MUCH faster... his walk is sick], as well as spin dash, and you can still boost in, it's just you can't boost back and forth forever.
I think in general his movement is fine. It could always be faster, but this post will primarily be about Boost.
Frankly, Sonic felt like an extremely annoying bait-and-punish character [bait you into messing up once, then grab/throw/dair/you die because lol dair is busted] prior, and by removing boost-dashing, he's instantly less obnoxious to fight.
I'm with you on the first part. Sonic could/can punish mistakes faster and further away than any other character. That makes sense for a fast character. I disagree that he's less obnoxious with the new changes; I think his playstyle has to be far more obnoxious now to be effective. You have to wait longer to find your openings; you still have to wait for them! I think Sonic should go in a direction that encourages aggression and rushing in at all times, a character with relentless pressure that forces people to think fast to keep up. Don't mistake me for saying that he should have safe and easy approaches. What I would prefer is for his approaches to have a high degree of mixup, while retaining a level of commitment. Once you go in, you shouldn't be able to instantly bail, but adjusting
how you go in is very important. Playing Sonic is often a game of circumnavigating hitboxes that are thrown out to stop you.
Here's one example of a basic technique with the old boost.
Option A is still possible; it's just a straight line Boost. Predictable, but fast.
Option B is no longer possible within reasonable timeframes.With option B, you continually approach, but by pivot-boost-pivot-boosting multiple times, you take 25-50% longer to actually arrive. If someone was hoping to forward smash you as you arrived, they'll perhaps swing too early and you'll get your hit in.
Option C is still possible, which is to stop Boosting entirely just out of range. It's tricky and takes timing, but will enable some followups. The 20 frame cooldown means you'll often be unable to boost-pause-boost to wait for a hitbox to finish and then go in. This isn't so bad, since many characters can't respond in that window, but without the ability to boost behind, you lose the option of back-throwing someone forwards by getting behind them. Sonic's grab is also slow enough that Fox (and some other characters) can cover themselves in a hitbox before you get in without boosting.
Also, playing lame is usually synonymous with "Playing optimally except I don't like playing optimally for whatever reason" (see: Falcon Melee tech chasing, Fox laser camping].
I think Boosting around and poking at anyone that tries to follow you does bear some resemblance to extreme laser camping. I don't mind playing that way against my roommate; we both like to win, and sometimes you have to run around occasionally throwing out nairs for four minutes to win the game. It's understandable. It annoys the
hell out of other people though, far more than when I could risk approaching on stage at equal or deficit stocks. I like that Minus is heading in a balanced, competitive direction, but I also think there should be compromises made to ensure characters can be played in exciting and engaging ways.
The reason you enjoyed boost-dance Sonic more is probably because Boost made it pathetically easy to rip a hole in someone's defenses, and made people naturally have a lot more opening because they had no choice [they have to swing for the fences or else stand still, and standing still is really hard given all of Sonic's tools, including homing attack being safe on shield].
That's a bit of a leap. I don't think turnaround Boost was the end-all approach option before. It was a useful option, but if someone's randomly throwing out forward smashes and hoping you'll faceplant into them, you don't need it to beat them! Last version I struggled mostly against Fox, Falcon, Lucario, and Wario. Characters with high aerial mobility with fast enough movement to keep up with and KO Sonic if I let off the gas. (Quick options in neutral certainly didn't hurt, of course.)
There are undoubtedly people who still find Sonic to be overpowered or not-fun in 4.0 despite the nerfs. Dair is still kind of dumb, but there are lots of dumb moves in Minus, and it's honestly not hard to avoid putting yourself in situations where you can die at super low percents to it.
This wouldn't be much of a feedback post if I didn't offer some kind of solution, so I'll share some brainstorming. I'm of the opinion that Sonic needs to be fast (naturally), aggressive, and risky.
3.Q Sonic was fast, aggressive, and not very risky. He didn't have to commit to his approaches. On the other hand, he had enough approach options that there really wasn't any reason to play defensively.
I haven't played as much 4.0b Sonic, but from what I've experienced, he's fast, but should be played in a safe and defensive manner. Fly around and try to Dair people when you can.
4.0 Sonic needs two things; more ways to commit, and even more incentive to actually do so. One idea I had was to remove the Boost cooldown, but cause Sonic to drift afterwards in whatever direction he was moving. I don't know the fine details of Brawl's physics, but this is what I would like to try for Boost:
When you initiate a Boost, you maintain some momentum, until you drift to a halt. Any Boosts that go against that momentum are slowed by the original Boost direction's leftover momentum. I don't know how simple that is to implement, but in concept it's just adding velocity vectors. There would have to be some sort of frame window where boost -> reverse boost causes the second boost to have lower or no carried momentum. In contrast, boosting, then doing an aerial, then boosting the other way would produce two opposite velocities. Hopefully something like this would encourage committing to a
direction while allowing for option variation.
I don't think homing attack needs to be safe on shield, though I'm actually not sure whether it is. It may depend on the approach angle.
There's more to come, but I need to fiddle around with the character a bit more.
TL;DR: Sonic's Boost cooldown should be removed, his physics should encourage him to commit, and I ramble when I ramble.