I would have to disagree with your statement about changing entirely. It's quite obvious SCV took after Streetfighter with all of the supers and what not, even the just guard system acts the same as the SF3 parry system. I think one of the devs said that SF3 was one of their favorite fighting games. Those were two ideas they took from another game which didn't quite fail. Sure some people hate it but they make due.
After having so many versions of a game, you shouldn't just off the back change the whole game around. That would be fail. You would probably lose the fans you already had, then you'd have to solely rely on new comers. They did a great job with the game an it can be played at high level. The gaming community can't be saticfied with anything. They're like most women, give them something and they'll want more or complain about what they got.
Every game has something to bitch about if wanted be. SCV dropped alot of it's original traits and has became Super Soul Calibur an on top of that, the movelist has been reduced. TTT2 is STILL a juggle fest. Although they've reduced the damage from T6 and made rage mode less gay. DoA5 still plays like DoA... besides the fact that they nerfed holds an added a sidestep system.
You can stop getting countered to death by poke and grabbing. That's why they call it the triangle system. It's a way around everything.