pherai covered most of the important differences between the SF4 and 3S engine. You can’t mash during a combo or blockstring like you can in SF4, that’s probably the most important. You’ve got to keep holding down back.
The inputs are stricter, so if you are used to doing things like df d df jiggle for shoryuken, you’ll have to retrain yourself.
Reversals are harder to time, and in general things like wakeup uppercut aren’t as good. In SF4 most DPs are invincible until they hit. But in 3S, most non-EX dragon punches are vulnerable before the first hit, so a meaty attack will beat it. On the other hand, 3s wakeup supers aren’t nearly as bad as wakeup ultra in SF4, so you’ll see a lot of beginner and intermediate players do wakeup super.
SF4 is full of link heavy BNB combos, e.g cr. lp > cr. mp > cr.mp > cr.hk, but 3S doesn’t really have these kind of combos. So you’re right, there’s a lot more focus on small hit confirms… Ken examples: cr.mk xx super; short short xx super; mp > super; and b.mk overhead > super.
I think one really important thing you don’t have to do in SF4 so much is pianoing the buttons. This is the key to doing most of the super combos easily in 3S, ensures that your super comes out as fast as possible. e.g. Dudley f+hk overhead, qcf x2 confirm that it hit them crouching, drum your fingers across lp mp hp, and your super should hopefully come out as early as possible for the combo. No plinking in 3s, just pianoing, which actually makes things much easier.
Parrying just comes with practice. Eventually you’ll have to consciously think about what moves you are poking with, whether they are parryable low, high or both. If you keep using the same attack (or worse, an attack that can be parried both ways), you’ll get caught in a lot of peoples frame traps, get parried, and eat a huge combo.
Otherwise, the basic flow of the engine is the same. Cancels work similarly, throws work similarly (lots more kara throws in 3s), the spacing and mixups. Good luck :tup: