Assassin/ds/ws (awesome class <3, most potential from 40-60, competitive from 70-80 but vulnerable to magic, and very powerful at endgame. One of the best and most fun to play in pve as well, can range and melee),
necro/demo/SL (kinda unique class takes some finesse and skill at low levels to play, gets to be strongest at endgame, best 1 on 1 at endgame, best pets, skill set more interesting than wiz and more important than gear,
sage/mystic/shaman (looks fun but time consuming, interesting class and only one that can kinda do it all, pretty good at doing it all at endgame,)
Cleric/prop/saint (don't understand the point of this class outside of buffs) maybe cuz only half seem to take it upon themselves to actually heal ppl and too many find its either fear or bust.
Pally/temp/crus (I like their tome and -dmg buff but outside of those buffs zerk class seems to do everything else better and more efficiently save tanking magic)
In between classes:
wiz/am/ava (kinda typical magic class, nothing too special about it, super powered in the 70 and 80 zones and super fun in 70 cuz of mad nuking abilities, but very bland skill set, gear or bust),
ranger/ss/HE (always enjoy playing ranger type class, this one is fun, especially in the low zones where its not all about mongose, but loses its unique charm as you level to ss it becomes all about pvp sets and mongose).
Berserker/wl/Dk; widest variety of gear and weapons and best combinations of tank and dps. But crazy squishy to magic. Too dependant and op on bullrush in the early levels and on gear in the later levels.