Playing Hyper Street Fighter Alpha really opened my eyes on the erosion of hit boxes and general effectiveness of normals. I mean, do Champion Edition Ryu’s standing mp while facing SFA3 Ryu, and have him do his. Champion Edition Ryu is ridiculously faster. Throws are better. Special moves are better.
Or take a look at Champion Edition Zangief. He’s pretty much the same as later Zangiefs, except with better range on his throws and more damage, of course. But he gets a few tools that he loses in SFA2 and beyond: a very fast lp (standing and crouching) and a very good crouching hk. In SFA2 you have to choose between a fast crouching hk or one with good reach.
As for comeback mechanics, those have been around since the original Art of Fighting. In Street Fighter 2 you took less damage as your lifebar went down. I’m not a fan of the more unsubtle comeback mechanics, but small stuff like the SF2 one I just mentioned are good.
In many Street Fighter games you gained meter faster from taking damage than by dealing it. I like this as a more subtle comeback mechanic. My opponent is already winning, which should be its own reward. This is especially true in games where you need meter as counters or otherwise to get out from under an overwhelmingly bad position. Some King of Fighters games take it further and give you meter when you block.
I think comeback mechanics are symptom of the ever-degrading damage level. In SF2 it didn’t take much work to come back from being at near death, while your opponent is at full life. With a lower damage scale, it takes several high-risk combos instead of a number of carefully-placed pokes to get back ahead. In Street Fighter 4, you’d almost never see anyone make that kind of a comeback without ultras.
The ease of landing a high damage combo is much higher now, but the rewards are less. In Super Street Fighter 2, if you get a jump in with Fei Long, you get a touch of death combo that pretty much wins you the match. This was the case with Ken in a few versions of SF2 too. However, your opponent had to be asleep at the wheel to let you land these combos. If you knew how to block cross-ups, Ken was almost never going to get his touch-of-death combo off. Most of the time, he had to settle for footsies and zoning like Ryu. If your opponent messes up a little, you can probably only get them with a crouching mk into a fireball (that they can block). Maybe 10% damage, if that.
In Third Strike, most characters can get maybe 10% damage off a badly-timed move with little recovery. A few like Chun-Li can get 40% damage off of almost any mistake, or even a lucky guess. This is far worse than Ken’s touch-of-death combos, because he was almost never able to land them. Stuff like Chun-Li’s 40% combo seem like the direction they took in SF4, with Ultras, and once again, not everyone can do it. This is also true in games like SFA3 where characters with devestating combos (or even 100% combos) that can punish tiny mistakes dominate the game. A 40%+ combo should only happen if your opponent messes up bad. This is what old-timers are talking about when they say Super Turbo’s super combos messed with the game in a bad way.