I like the aquamancer idea, something that comes to mind is the maormer connection to snakes and maybe slithering water snake attacks might work. Or something else snakey.
Class wise and not listed in the poll I like the idea of Clockwork Articifer who use mechanical devices to perform attacks and has Clockwork summons. Maybe lightning attacks but not like the sorcerors. Could also be Dwemer and use tonal attacks using sound to destroy.

Most of these are not really class material.

Bard - A class mostly defined by it's non-combat oriented skillset is ill fitting in a combat oriented MMO. Could be a skillline tho, but that opportunity was already missed with the Bard's College, but you never know. Alternatively it could involve Tonal magic, but that's an OP skillset reserved to Dwemer.

Monk - There's two approach to this: either you want fists as weapon in which case it's more fitting to be a HtH weapon style or you want DnD style spiritual martial artists, in which case we already have those, they are called Dragonknights.

Spellsword - It's not really a class, but a weapon style. I mean sure, it was a class in past TES titles, but everyone sees it as the class that wields magic AND sword. So it's best implemented as a new weapon line.

Aquamancer - well, that's not something i ever saw anybody wanting, like ever. Water magic technically does exist in TES, you can see Nereids cast water geyser, Maormer are capable of manipulating the sea and Dreugh also prob could have related abilities, but it's not really a well established mainstream power. It would prob have massive lore implications.
Tbh, i don't think water can stand on its own as a class theme.

Btw, this thread is a year old so nice necro, but I guess it's relevant since it's about making predictions for 2021

Bard, but only if every spell is accompanied by "Starlit Bride of Alinor" sung by that annoying man in the crafting area.

wtf is Aquamancy?
the term is HYDROmancer as in manipulator of anything water.

besides i personally dont want to see a new class, i want spell crafting so we can start shaping the class many folks WANTED ages ago so that we can do stuff like:

• by altering abilities elements(so changing a magicka or fire spell into frost or shock, etc)
• damage type (so a magicka spell becoming physical as an example)
• change secondary effects of spells (so instead of a snare we can alter an ability to apply fracture, taunt, healing block, etc)
• change some abilities from a heal to a damage spell or damage spell into healing

that way we can make the classes WE want without the need of an aditional class and allowing us to adapt our favorite abilities to better fit themes, adapt abilities so that we can coordinate better with other players to syncronize better so many classes can hopefully stand out better at tasks they werent origionally built for like tank templars or healing sorcerers or even something as wild as an actual healer nightblade

edit: just realised someone necromancered this thread -_-

Bard? No way.. It's already irritating that people in towns and world bosses are using lute here, flute there 5 on drums..
bard would be focussed on "music" magic and makes me think of FF, so no.. thank you..

Spellsword? So basically a sorcerer with a sword? something you can already do? Sure it's not a real fleshed out spellsword but you can get pretty close with a stamina sorcerer also known as a Mage Blade.. If we add something, let's add something new and missing from the menu.

From all the choices I would vote Monk. A class focussed on matrial arts, way of the fist, crounching tiger hidden dragon type stuff would be something new and interesting. This could be very unique and cool if done right..

But... If I could name any type of new class that's not on the list (we got a limited choice here) then I would rather have classes like:

Warlock: Poison magic, Curses, Green flames(corruption) and Illusion based pets like Spiders, wraiths or a shade version of symphony of blades. could be channel heavy class. And yes, warlocks do exist in Elder Scrolls lore.

or

Witchhunter: Ranged/bow type skills (like the NB Grim Focus). Anti-magic type skills that drains magicka from foes. Passives that increase potion strenght by 25% and has other skills like a damage shield, summoning Aggro taking decoys that do not do damage, soul link magic (bind foes together and main target transfers 30% of damage taken to other linked enemies ).

You know, stuff like this.. actually something new and exciting, without the complicated mechanics and stupid "this skill is an criminal act" type stuff, like the Necromancer.. I was really excited when it was announced but after trying it for 4 times and forcing it to like it (but just couldn't), I gave up on the class. Too weird with the "needs corpses" and the enemy needs to be in the beam and stuff..

They could made it so much better by just having skill like "raise zombie" and morph it into armored zombie. Then add skills like Health absorb, Fear, Wall of Bones, Bone Coffin (stun), Summon Flesh Attronach (permanent pet) and things like that.. but no..

anyway, I'm going off rails here.. but that would be my pick.

Monk/Unarmed, Bard, and One-handed, with the other hand casting magicka abilities would be great skill lines to add to existing class.

I would like to have more Destruction, Illusion, Mysticism, and Alteration magicka added, whither by a new class, or skill lines. Either way we would need more character slots.

i can't wait to see what comes in 2021.