The final installment of the previous posts.
But first, another interesting type of air movement is short jumps or hops. In the games that I've experienced them in, such as Jojo's Bizarre Adventure, Garou:MotW, and CvS2, I've been rather fond of them. But I believe they can just as easily go horribly wrong if not properly balanced, such as what is seen in a lot of SNK games where shorthops are basically all anyone does all round long.
In my opinion, it shouldn't be difficult at all to balance this mechanic though. Things like adding a landing recovery, narrowing the jump arc, slowing the ascent, and disabling defensive options during short jump state are some obvious "fixes" to a potentially problematic mechanic.
The question then becomes, are they necessary to add at all, particularly in a game that has other types of airmovement. Personally, I would say yes, especially if given some incentive to use them such as air special cancels or the ability to super cancel the ground recovery, or other such things. Though with these in place, I feel that they also shouldn't be totally risk free or difficult to anti-air if anticipated. With it set up like that, I believe it becomes enjoyable to attempt risky short jumps when you get inside your opponent's head with a read. And likewise, enjoyable for the opponents that read short jumps and are able to punish them, and so on.
But, back to air movement in general. I think what it all comes down to is the implementation of many different mechanics that can make or break air movement.
Although I may get hated on for saying this, I feel that MeltyBlood and Scarlet Weather Rhapsody (and certainly BigBangBeat) failed in these departments, and GuiltyGear may have on some level as well. Even though MeltyBlood and GuiltyGear are rather popular and enjoyable games, I feel the footsie game is diluted, watery, linear/predictable, and boring. As much as I have played MeltyBlood and continue to play it even now, I think the footsies in that game are much less what I would consider real footsies. Instead, I would say that MeltyBlood relies almost entirely on "king of the hill" fighting, which is basically just vying for height supremacy, and "fishing", which is basically just sticking out pseudo-random high priority pokes while flailing around in the air.
Games like MB and GG tend to be very "hoppy" due to the airdash and doublejump mechanics, and not much classic style footsies really go down. Instead, both players are bouncing around like rubber chickens with their heads cut off on opposite ends of the screen. Eventually some one moves closer, some one gets hit or blocks, and then the rushdown-mixup game occurs. Guilty Gear has a more interesting dynamic to it than Melty Blood, though, which is the projectile game. The majority of the cast in GG has some slow moving projectiles that they can use as both cover and shields, as well as zoning and controlling space. While projectiles exist in MB, not every character has them and even a lot of the ones that do have them hardly use them for that purpose.
But I've said it before and I'll say it again, even things that we can deem as "stupid" can be enjoyed -- such as the children's game rock-paper-scissors can actually be fun for a while to some people, even though it's not exactly action packed rocket science.
Even I am able to look past the flaws in MB's air game and still enjoy the game as it is on some level. But not a set goes by where I don't end up thinking at some point "well, that was stupid, why did I just play that game?".
But to me, I'd much prefer to have fun where I know fun can be had. Such as the doublejumps that exist in certain versions of Monster and the airdashes that exist in Immaterial and Missing Power, since I know the way things were done in these games only add rather than subtract or dilute.
To me, these mechanics not only make sense on paper, but are actually really "fun" in practice, which is pretty rare in high-level competition in fighting games these days, IMO.
In closing, shorter/lower/slower/more risk = better.