Every class is decent enough to play, but for the purpose of racing to 50, or getting extremely early raid mob kills certain classes are more well equipped. This is a rough guide I've worked out, I could be wrong on some of these classes as I haven't actively been raiding/playing for a year now. When I made these tiers I did so with both grinding/raiding efficiently in mind. If we were to just look at raiding or just at grinding these would be moved around a bit.
Tier S is for classes which way over-perform and can make a big difference if we use them in aggressive numbers for the grind and raids. These classes typically perform well even with little or no gear or outperform other classes in areas traditionally outside of their "archetype".
Tier A is for staple classes that perform more or less exactly as you'd expect, they're some of the best options in whatever category they represent, choosing these is always a solid/great option.
Tier B is for classes that are only good in either groups or raids, but not both or classes which are very gear dependent and are not "staple" classes.
Tier C is for classes which due to nerfs or the server timeline will almost always be sub-par compared to other classes.
Tier S:
Monk - Great DPS from 1-65 they will be awesome for the entire length of the server and require almost no gear early on.
Enchanter - Once they hit level 11 charm pet DPS is pretty much the best there is, having one is a must for each static group, having two or three could be even better.
SK - These guys are busted. In some expansions they'll be the best DPS in your raid. Plus FD, snap aggro, harm touch and loads of other utility.
Tier A:
Wizard - Great DPS from 1-65, they will be great even naked and outside of a few select zones (PoSky) there is never a downside to having them.
Cleric - An obvious staple of any raid or group, like warriors there is nothing more to add.
Shaman - This is a staple class that I wanted to put in S tier but with the recent nerfs I'm tentatively calling them A. Slow is such a huge boon, and obviously the buffs they bring to the raid are amazing. Their pets have also avoided the Necro/Mage nerfs. I'm not positive a Shaman can be the main healer for a group for the 1-50 grind, but maybe partnered with a Paladin tank they can float it. Some of the Shaman mains here can probably weigh in better than me.
Warrior - Not much to say, after we get 50 + some gear they'll tank 90% of everything we ever fight. Once they get Defensive in Kunark it's a wrap. They are probably the worst of the three tanks for the 1-50 grind though.
Bard - Another staple class, bard songs are as useful as ever with resists/haste/mana regen and they're solid pullers. They are not going to put out a ton of dps alone but they improve the whole group and can do some good CC in a pinch.
Necromancer - Their dots may be a bit underutilized during the grind to 50 since mobs die so fast, but their pet remains solid and in zones like Lguk they'll be able to charm. If they don't eat a nerf like Shamans/Druids they'll be amazing DPS on a lot of the MoTM 1 raids where mobs have tons of hp relative to the overall DPS of early raiders.
Tier B:
Paladin - Great group tanks for 1-50, they can off heal, snap aggro and do some very light CC w/ stun/root. Sadly in raids the Warrior will out tank them and they'll never come close to the DPS benchmarks of the SK.
Mage - Mages are great for the early grind, they have powerful pets and require no gear to put out great DPS for the group. However they are sub par in early raiding if you've got more than 3-4 due to Mark of the Old Ways.
Ranger - They have uses, but during the grind to 50 they are very gear dependent and even with gear other classes will outshine them. By Luclin they'll be very good, in PoP they should be incredible.
Tier C:
Rogue - It's hard to think of a time where replacing a Rogue with a Monk wouldn't be a strict upgrade, especially during the leveling process and server first fights when our gear is the biggest obstacle.
Druid - The most important role for the druid was already mobilization, with recent nerfs it seems the class has taken a big hit to DPS and still remains incapable of solo healing a group. This is a shaman with worse buffs and no slow.
