Fighters are easy: Juggernauts, Divers and "Light Fighters" are all very distinct. Assassins are tougher though; they all have pretty similar tools and serve very similar functionalities. It's hard to even distinguish differing strategic niches.
If they have distinguishable sub-classes, or if you think they will have once they are properly differentiated, what are they?
Tenryushin2 votesI would say Stealth Assassins, Mobility Assassins and Suppress Assassins
DeathBurst1 votesOh, Stealth vs Mobility is a nice think I didn't think of. What do you call Suppress exactly? Because the CC called Suppress isn't exactly used by Assassins (Malzahar, Warwick)
Tenryushin2 votesI do think Malzahar could be on the suppress assassin line but for me a prime example of a suppress assassin would be Annie. She has both the lockdown and the burst.
Guyy Fieri2 votesWe're getting a little too broad with the term assassin....Annie and Malzahar are not assassins
DeathBurst2 votesYep, I agree.
But it's true that there is a fine line between Fighter-divers / Assassin / Mage-burst.
An important distinction is, I think, that Assassins have more mobility (compared to burst mages) and less DPS (compared to divers).
IcyPepper2 votesThe most obvious class is the mobile assassins, who get in and get out. Zed, Katarina, etc.
I'd say that there's also dueling assassins who excel in being sticky, like Master Yi.
Then there's diving assassins who get in, burst, and usually have some tool to survive but don't have a "free" escape. Talon I would say is one example, and since Vi is a secondary assassin (but almost always built a bruiser) she has the kit and playstyle of one as well. Diana probably counts, since she has her W for survival but has no easy out unless she ults a monster or minion.
And stealth assassins as well, such as Shaco and Evelynn. Twitch and Vayne as well, I guess.
Hayaishi21 votesAssassin fighter. Duh like Fizz and Irelia
Guyy Fieri5 votesIrelia....not an assassin.
DeathBurst1 votesNot sure there will be subclasses. Look at ADC, even after the pre-season rework, they don't really have distinct sub-classes. Maybe Crit vs On-hit vs Caster, but it's not clear. Also, there are ~40 fighters, versus ~15 Assassins. They don't need subclasses as much.
DeathBurst2 votesI think there will be "niches", though, with 2-3 champs per niche. From the top of my head, with examples in their current iteration:
EDIT: a few more, some stolen from other posts in the thread, for the sake of exhaustivity :p
charcharmunro1 votesWell, there's the all-in, 100-0 Assassins, dunno a good term for them, though: 
, 
, 
and probably some others.
Then there's the Assassins that rely on catching an opponent out of position: 
, 
, and maybe some others I can't recall.
Then there's the ones who bring more utility, like... Uh... 
? I don't... I don't play Assassins.
BlackEyesBlue1 votesHigh damage/suppress/stealth/mobility. (Though certainly not ALL at once.) BUT!!...
This should be coupled with HIGH risk!!!; Something most assassins right now, really aren't...
A lot of the assassins in League right now are SO freaking safe! and can dive virtually risk free because of all their escape potential. 
and his low CD total stealth just feels cheap and unfair. Not to mention having soft and hard CC in his standard kit. is a perfect example of doing EVERYTHING assassin like too safely.
In the past, I've called 
the truest assassin in the game. She's squishy, lacks any CC outside her ult, and her stealth can't be used defensively; so a carless engage will get her killed. As opposed to all the above mentioned who have tools to escape a gank gone bad. I really wish more assassins were like this. Highly crafty but with notable weaknesses, and at a disadvantage if caught out.
AyRe CoNteMpT1 votesassassin is allready a sub-class.
fighter is the general description for champions who want to be in or near melee range for an extended period of time. for example: garen. he is a prime example of a fighter.
now dividing fighers into sub-classes like juggernauts etc is generally okay but not really useful due to the lack of distinct roles of most champions (a good thing).
for example, pantheon is a fighter because he wants to be in near-melee range for extended periods but he is also an assassin because his damage is one quick combo and he has no abilities that support building defensive items which "forces" him to build damage and be squishy so in a duel, he is rather weak as all assassins are and his only chance to deal his damage properly is to catch someone off guard, i.e. assassinate.
leblanc is a mage as she uses spells and ability power aswell as mana but her abilities are one quick burst of damage on a single target/very small aoe so she is mainly used to kill a single target very fast.
viktor is a mage too for the same reasons and his combo can deal just as much damage, if not more, just as fast as leblanc and has alot more aoe, utility and range. what he doesnt have tho is the mobility and thus, he is not an assassin because the area around him in which people count as "in kill range" is much lower than any assassins. he also has no way to get in and out quickly, so he cant be an assassin.
zed and fizz are mainly assassins as both of them deal their damage quickly to one target but dont neccessarily want to stay after using their cooldowns.
there sure are different types of assassins but they all generally do the same: put themselves up close and kill quickly, then get out. no real need for sub-classes. all assassins are somewhat mobility assassins. malzahar is not an assassin, he is a mage and even tho he can assassinate very good, he simply isnt one. if you facecheck a garen, you will pretty much die and he can assassinate wonderfully but he isnt an assassin either.
Wolfram Oxford1 votesFighters would be like juggernauts, bruisers ,etc.. Assassins can't really come up with a sub class because they all assassinate people using the same method; dump all of your spells onto them. Maybe if they get around to an assassin update they will add some variety to the mix and how they kill their target. Hopefully we see 
