It seems I always get hit with the really hard questions when questions arrive. The subjecting of cancelling normal attacks into other normal attacks was posed. Unfortunately, this is a really sticky subject. There's lots of ways this can be handled and each way has a really significant effect on how gameflow works.
For example, there's games like MeltyBlood that allow you to cancel any normal attack into any other normal attack. The rules that apply are basically that if the strength of the attack is lower than the previous then you get a damage penalty via timed proration.
Then there's games like GuiltyGear and the Capcom X-Men/Marvel series which allow you to cancel normals within specific rules. Generally you can cancel lower strength attacks into higher strength, or from punch to kick or visaversa.
And there's also games like Akatsuki or Jojo's Bizzare Adventure and various other games that allow you to either cancel or link light/weak attacks into medium attacks.
Then there's Vampire Savior. I put Vampire in the spotlight because the game uses special rules that I feel are rather interesting, though problematic for other reasons. First of all, the game allows you to do a "magic chain" like the Capcom X-Men/Marvel games where you go from punch to kick and from light to medium to heavy. Except that, if you cancel a normal into another normal, you are unable to cancel the second attack or any following attack into a special or super, except for very specific exceptions. Now, I know there aren't many people who read this blog, and those that do probably have quite a bit of gaming experience. But please bare with me.
The reason this is such a big deal is basically hit confirmation. But it's a good deal more than that, depending on the game and the characters, and several other factors. I don't think I can even begin to really portray the implications of hitconfirmation, unless you have experience in both the performing and receiving ends. But, I'll try.
To use a very extreme example, we can say that a game with totally free cancelability would/could result in some very tragic gameplay. Reason being, any hit that is blocked results in no punishment at all, and any hit that connects leads to several more hits which give the player more than enough time to realize that they are successfully hitting the opponent, which allows them to decide to cancel a hitting attack into a super (or special) for massively more damage.
Thus, we are back to the fighting game, where the players are attempting to hit the opponent as best they can without being hit in the process. The problem here is that the risk/reward ratio is incredibly unbalanced. But also, the ease at which you can take full advantage off success is also really unbalanced. What this results in is players using light attacks as much as possible with little to no risk, but with the reward of a full combo on successful hit, without any need to really pay attention to whats happening in order to recognize the situation where it's okay to super.
That might be rationalized by arguing about the subject of the first step. A better player will hit the opponent first, and therefor the better player rightfully reaps the rewards. But the bigger problem is that it doesn't end there. If you're able to combo off of anything and are able to combo into anything, then you are most likely able to get a knockdown which leads to mixups.
Again, in a most extreme situation we could say that a game would allow players to combo off any hit into any other hit, leading to a knockdown. And this leads to hitting in 4 different directions or throwing, which is a 5-way mixup. Either hitting from the upper left, upper right, lower left, or lower right, or throwing. Any of these hits, when successful, loop back into the same combo and knockdown and mixup.
This is how a lot of momentum-based games like GuiltyGear and often MeltyBlood pan out. Players fish for random attacks either in the air or on the ground. On successful strike/block they gain initiative/momentum which leads to them performing a series of attacks that can result in the opponent being hit, which results in a combo into knockdown, which results in a 5-way mixup and back into itself. Then add rever-safe meaties and you have a massively momentum-based game.
This isn't just limited to the newer games though. Games like SF3:3s have this as well. Such as Ken knocking the opponent down and going for a 5-way into super and back into another 5-way. But then, I've always said 3S was a highly momentum based game in the first place, even without normal-chains it's still possible.
But to put it into perspective, who really needs a 5-way mixup and normal chains when you have Chun-Li who has throw/low medium, where throw loops back into the same mixup and low medium is confirmable into super. A simple 2-way mixup rules that game simply because she can hitconfirm one of her options for about half your lifebar, and her other option resets the situation (so does landing a super, actually).
But, back to Vampire Savior. That game isn't without its flaws, but it also has a lot of really good mechanics as well. In this case, if you chain a normal you can only continue to chain it, but if you only use one normal then singular normals can be special/super canceled. That means hitconfirmation isn't brain-dead simple. You could confirm off a mixup, assuming the first successful hit was the jump-in high, and then you confirm that hit and combo into a ground normal and super. But if the hit was a low then you don't really have time to confirm it, so you have to chain.
But, outside the mixup situation we have the defender of the mixup and footsies. During both, the reward for mashing out low light attacks isn't as good as using a medium or heavy attack which are potentially confirmable into specials/supers. This is a good thing because the defender shouldn't be rewarded as much for just option-selecting a defense.
Here's the kicker though. A lot of players actually like/enjoy the mechanic when it's unrestricted. But eventually it gets to the point where it's not so fun anymore, since no one's having fun playing the game. For example, we could take a look at some 3D fighters that allow you to chain jabs, which confirms into a rekka, and the super cancel the rekka for super damage + knockdown. Given the choice, most players would prefer a character that could that as apposed to one that can't, but if the game is full of characters like that the game becomes really stupidly boring really fast.
So what about Akatsuki and Jojo's? Well, the answer should be clear. What you're able to combo off from a medium attack determines if the mechanic is good or not. It's like saying, what if we give Chun-Li the ability to chain c.LK into c.MK. Likewise, Mycale from Akatsuki and Devo/Kakyoin/O.Joseph from Jojo's get the ability to confirm light attacks into mediums, then super cancel for massive damage. But, other characters in both games have the ability to chain/link lights to mediums and aren't rewarded nearly as much for it (Mariah/Kanae).
But in my opinion this is just character balance trying to compensate for an unbalanced mechanic, causing huge rifts in tiers. Eventually time shows that the characters with the better cancels end up as top tier characters. But why would anyone want to play a hugely gimped character unless you find a very interesting/reasonable way to make that large of a compensation.
In closing, I'm rambling. So I stop now.