Rogue: Make assassination a ranged dps spec, using a ranged weapon. Also gives hunters competition for weps, which they don't currently have. Make sub a pure magic damage spec, and keep combat as it is. Buff our damage in all aspects to bring us up to par with ww monks. Give us a 4th spec that allows us to tank.
Hunters: Make marksman a nonpet, ranger style. Make survival a pure magic damage spec. Make beastmaster a physical damage, melee dps spec. Add a 4th spec for hunter tanks. Could be cool if you parked your toon in the back of the room and controlled your pet to tank.
Mage: Make fire a plate wearing, melee dps spec like a battle mage. Keep frost a pure caster. Make arcane a healer. Add a 4th spec to tank.
Warlock: Make demo a leather wearing melee dps, aka a demon hunter. Don't know what to do with dest/afflic, but add a 4th spec to tank or heal.
Look, blizzard is done with the hybrid tax. As pures, we no longer are going to do more damage, so the only logical option is to make the 4 pures hybrids as well. Give us the option to perform other roles, give us the option to que tank or healer to avoid the long ass dps ques. Also tune our dps specs so we can excel in all situations. Theres no reason that ww monks, dks, ferals, boomkins, etc should rip us on single target, rip us on cleave, rip us on aoe in one spec, while we have to switch specs just to be viable in one situation. Other solutions for rogues, as its the class I play: Make blade flurry baseline, not combat exclusive. Buff our single target, and bring blade flurry cleave up to ww monk level.