The balance of super turbo has always been that every character has at least two or three bad matchups, if not more. It isn’t that all characters are internally balanced against each other character. It’s that every character has a counterpick, and all matchups are winnable (Except Cammy v. Honda, and Dhalsim vs. New Sagat, at top level play – two screwups is pretty awesome in the grand scheme of things…more balanced than any other fighting game).
There is also a wide variety of matchups types, and character win/loss diagrams. For example, Chun Li had very few bad matchups (Sagat, Ryu, perhaps Guile) but they were not very bad, but on the flipside almost none of her wins were huge (excepting Gief). Dhalsim had a number of terrible matchups (chun, claw) but on the flipside, beat other top level characters soundly (O. Sagat, Ryu, Bison) and utterly dominated a lot of characters 7-3 or worse (guile, fei long, ken).
Obviously different character are flat out better than others, but every character has a place (Fei Long, for instance, sucked generally, but could do 70% combos out of nowhere and pretty much had a shot against anyone, even Dhalsim (probably his worst match)).
In HDremix, if you add Akuma in, he’s obviously not a character on the same level with everyone else. He has no bad matchups. The majority of his matchups are large wins (7-3 or 8-2) and some are 9-1. His worst possible matchup is going even with Dhalsim (which I still do not agree with–I’d say it’s more 6-4 Akuma).
He also has plenty of Chaos factor, like Fei Long and Bison do, but he gives up nothing to get it. He can do 60%+ combos with crazy dizzy chances, in a safe, virtually risk free fashion on half the cast. He can beat any character in multiple ways – he can go nuts and do risky combos, or he can turtle down like crazy.
He’s kind of like a much, much much better version of Deejay (crazy combos, good turtling, very few bad matchups). Deejay pays for it with a hit-or-miss reversal, having to charge, and very few big wins (most of his wins are slight edges, 6-4 or 5.5-4.5).
Akuma pays for it with nothing. Hell, even Chun - the most universally winning character other than Akuma - pays for her power, with having to charge, a shitty reversal, and getting punked by Ryu (if you’re going to lose to a character, Ryu is probably the last losing matchup anyone wants).