How many Black Knights (Black Wings Generals) are there really?

Also makes me think Orca is from Ariant, or around there, since that's really the only place you can find the Desert Rabbits she's appeared to have mutated (other than Henesys, which has Moon Bunnies, but her bigger henchmen appear to be Desert Rabbits mutated).

There's nothing similar between Orca's henchmen and Desert Rabbits other than that which is intrinsically inherent from them being rabbits.
There are rabbits all over Maplestory: Korean Folk Town, Ariant, Chryse, and Ludibrium.

As for Goire, he needs to be a gigantic Krexel-type general, since his minions appear to be trees, making him seem Terra based.

Like Orca is a giant rabbit?

On a side note, you use the word "need" far too often in places where "I would like to see" would be more appropriate.

If we factor in that Mikhail is the captain of the Cygnus Knights, in a story where our first-person view Cygnus Knights don't exist, he'd be the only one capable of killing Eleanor, due to his unwavering loyalty to the Empress. This would make him the canon killer of Eleanor.

The canon killer of Eleanor is an unnamed Cygnus Knight.
Our first-person view of a Cygnus Knight does certainly exist.

the Thief and Pirate legends (whom from a source I hear are to be named Boralis and Krytus - could be hugely wrong on this though)

Don't worry; you are.

-Mikhail is the oldest and wisest member of the Cygnus Guard, second to Irena, with Eckhart being in the middle, and Oz being the youngest. Because he's been serving Cygnus for quite some time, even long before Nineheart, he can at least break loose of Eleanor's curse, and be able to kill her.

But he doesn't because he's frozen in carbonite.

Since Black Mage probably lost his humanity during the Magatia Immortality incident and became a demon, it makes sense to call him Asmodius, since MapleStory paints him as the penultimate evil.

It makes more sense to call him the pineappleing Black Man.

In my eyes, in a fight you win if you kill the other person, especially if we're talking wars here.

By that definition, virtually no war in history was ever won.

Somewhat offopic: Has Alcaster been given any new storyline in the Mercedes or Demon Slayer quests? He was arguably the most important person of rebuilding Ossyria after Black Magician's defeat (built Magatia, made Orbis float, sealed Zakum, etc.), would be weird if they neglected him now. The Magatia storyline clearly hinted that he stole his alchemy powers from Black Magician's studies, wouldn't be surprised if he had secretly been an old follower of him or something.

I would love to see Alcaster's story expanded. As you said, he clearly has a major role in the story, but he basically is just used a a All Cure hawker.

EDIT - @Viaje: The only reason I'm doing this sort of speculation is because Nexon has YET to reveal any official lore for this story; and lore is the kind of thing we need to make SENSE of this damned arc. I mean, Neople and Nexon are working on DFO lore, and Mabinogi/Vindi have their lore built in, albeit not finished; why is Maple the only one without an official lore written out?

I don't think you know what lore is.

Such a deep topic about something with so little info.

Which is why half this pomegranate is being made up on the spot.