ADC: squishy high damage dealer with good kitting ability. Tank: Very Durable very low damage dealer with the superior crowd control. Mages: Squishy high damage dealers with moderate kitting and moderate crowd control Bruisers: moderate to somewhat high damage with good sticking abilities and moderate durability. Assassins: High damage with no cc or very low cc and high mobility.
What we have now is not what the roles should be doing
you have an extremely skewed view of what a role is.
tank, mage, "bruiser", assasin < these are classes not roles.
adc and bruiser arent even official terms. those were coined by the community.
plus, shoehorning and enforcing a meta isnt good.
Role =/= Class
What a character is supposed to do should depend on their role and not their class... Forcing a monolith on the classes will make gameplay stale.
Ex: 
These are all support and, while there is certainly some overlap, the roles are different... You don't pick leona to keep your adc safe, you pick her to snowball the adc. Etc.
Most of this game only appears chaotic because a large amount of ppl don't really know how to play.
Roles are Top Jungle Mid Support and Adc.
Classes are Tanks Fighters Assasins Mages Warden Enchanter and Marksmen
Bruiser is a popular term used in the community as it....more accurately describes how much damage they can really dish out. Term fighter isn't exactly precise in describing what the actual class does lmao.
