Well truth be told, new classes wouldn’t work because of balancing, and there are some classes people would like to see in game but due to that reason they won’t. So class skins are a pretty easy idea that would e.g. give the impression of playing a necromancer from Warcraft 3 while really playing your warlock. No need to change the names of the abilites, because maybe it would cause confusion, although it could be like the Lightspawn Glyph, where it says “Lightspawn” and somewhere within the tooltip it says that it is really the Voidfiend ability.
Besides, there is already a class skin pretty much, with the green fire Destro Warlocks, so it wouldn’t be anything too difficult.
So here is a list of possible class skins:
The Necromancer
This would easily be a class skin for Demo Warlocks. Could be for other specs too but let me give you the main idea: You replace all the Legion minions with Undead ones, for example the Voidwalker would become a Ghoul, Imp would become a frostwyrm whelp, Felhunter would become a Nerubian, Succubus would become a Banshee, Felguard would become a Skeletal Warrior (like Mor’Ladim), Doomguard would be a Gargoyle, and an Infernal would be an Abomination. Dreadstalkers would be Darkhounds. Demonic Tyrant would be a big shade like those in the Maw (https://www.wowhead.com/npc=179735/torglluun). All fel abilites would be recolored like either Maw magic or Maldraxxus.
The Tidesage
Frost mages would be ideal. Their Water Elemental would become like either Aqu’sirr (https://www.wowhead.com/npc=134056/aqusirr) or stay the same. All frost abilities and especially Blizzard will change to splashing water (the assets are already there from BFA).
Priests of Elune
This is one more similar to the green fire of the Destros’ because it would be basically recoloring all Priest abillites with the color of Elune’s light.
Spell-Breakers
This could be a class skin for every race that can be both paladin and mage (could be Blood Elf only but would probably be unfair). Protection paladins would be the ideal spec for this class skin. Concencration, Hammer of the Righteous, Shield of the Righteous, Avenger’s Shield and Avenging Wrath would be recolored to purple or something, Divine Shield would get the model of Prismatic Barrier, Judgement would be Arcane Barrage’s model etc etc.
Have any other ideas? Do tell.
Transmog Options
-Hide weapon option for Worgens, Casters and Monks
-Transmog each hand seperately
-Pistol transmog in the guns section for hunters (can use the model from Outlaw Rogues).
I’d personally love for some alternate animations for MM Hunter that are less elf themed. It feels out of place seeing my Dwarven rifleman shooting off all these purple sparkly effects that were clearly designed around arrows (Also, while I’m on the subject, I want to turn my gun back into a gun, not just some pea-shooter that makes a lame plink sound).
I’d also definitely support more cosmetic choices for things like Shaman and Mage Elementals - I’d love to be able to summon more sandy, desert-y Elementals with my Vulpera, or have my Pandaren summon the kind of Elementals we saw in Pandaria!
But that’s the point: Unholy DK’s are melee necromancers, so as a SKIN, Demo Locks would have the option to be the classic ranged necromancers. That’s literally the whole concept of the idea: to make a class look like something else.
I don’t think turning Demons into Undead as a cosmetic option is something they would do because there are spells which interact specifically with those creature types. Making them look like something else could be confusing. This is why all of the pet glyphs for Warlocks are all still variations of Demons, and the pet Glyphs for DKs are variations of Undead.
I’m all for getting class skins and stuff, but if one classes skin is “now you’re a DK”. That just feels lazy and unoriginal since they literally just become another class.