If it's anything like the other sages, it'll be a hybrid Black and White mage with some unique augments to the spells. :o Depending on the source, it could be a 'heroic' version of red mage, or it could be an alteration of red mage. We'll see! (Hopefully it's something entirely new)

OH! and this is a really neat art piece, kudos to the artist c: Lookin good, birb

Its a healer class :P
from what the announcement said, it will probably specialize in barriers, buffs and the like.

I don't play 14 myself, no money for the expansions and the monthly payments, so I only know surface details. Sorry :P

No worries
but yeah, sadly classes are hard coded into a role*, though the way they play can be very different (funny enough, I hear ff11 was more open with classes and stuff)
and I avoid it for a long time for the same reason and having no one to play it with; then my boyfriend dragged me in kicking and screaming and we now both love the shit out of the game :P

*Healer (soon to be divided into pure healer and barrier healer) Tank, Melee DPS, Ranged DPS and Magic DPS.

I played FF11 and correct, each class had super unique things. Blue mage was a jack of all trades, but the limit break (unlocking 50 to 55) quest was a NIGHTMARE. Your opponent was your teacher... A blue mage... Who had level 5 death... which... you can only do it at 50... And they also had white wind, which always healed them for 9999... Which you wanted them to use because you could out DPS that normally. They also had spells you could NEVER obtain because they were higher level, and they would do REDICULOUS damage. They also had SELF DESTRUCT if I recall, where it was ALWAYS 9999 damage, so you always died from that too. They had a wind spell (I think Aeroja?) while you only had Aera (second level) so yeah... You could only do it once a week, and that was with a paid sub, and I failed it several weeks in a row just because of things like level 5 death. They eventually fixed it to have unlimited tries (not time gated) and made the AI less aggressively painful I heard, but I never returned due to that bullshite.

*ANYWAYS*

Yeah, the FF11 classes were more true to their older counterparts. Dragoons were a weird temporary 'pet' class, but most other classes were true to themselves. Ninja dual wielded and threw things. Blue mages learned spells from enemies and you had to hunt for enemies to learn your abilities. White mage was a support with heals and barriers, some holy damage. Black mage was brutally strong but fragile as heck and suffered from "Statue" problems (Stand still to cast a spell with a long cast time, bam, dead because you didn't get out of an AoE). Bards were buffwhores XD and so on.

EDIT: OH YEAH! Red mage was literally just white + black mage with some attack skills. It was weak as heck early on but got stronger as you trudged on.

sounds really complex!
but yeah, 14 is far more arcade-ey by comparison
Red mage, for example, is straight up DPS, having to balance a gauge of white and black manga that they can cash in for their melee attacks
Mostly by using the elements exclusive to white and black mage (white - wind and earth, black - lighting and fire; Though actual black mages also get ice as an element)
though they do unlock a healing spell later on

oh, and also... flying magic swords :P

We know what it does
it heals
with the power of GUN

alternatively, it GUNDAMS