Best 4 person all caster/priest group
 

And go

Shaman Enchanter Enchanter Cleric. If you are planning on doing Fungi Tunic camp then probably swap 1 Enchanter for a Necro, so they can pull.

Oh this one is easy. Enchanter, Cleric, Mage, Necro.

Enchanter focuses on dps/slows & mez when needed
Cleric will be nuking most of the time but cheal is cool too
Mage provides malo/dps & coth when needed
Necro primary puller/cc & summon/shadowbond when needed

Enchanter, Enchanter, Enchanter, Cleric.

3 charmed pets, cleric for oh shit. Extra chanters as disposable pullers

This is the answer. But I'd cut the Shaman for a Mage.

Unless you need CoTH, Shaman is objectively better. A Torpor Shaman is a really good way to reduce how much mana your Enchanters and Cleric are using. They Malo and Slow (so the Enchanters don't have to), Heal (so the Cleric doesn't always have to) and self-regenerate their own mana. Plus the buffs and heals help keep the party going. If you need a pet for tanking charm breaks, Shaman pet can tank just fine: https://www.youtube.com/watch?v=umuVBewCNgY . They can DPS fine too if you are doing well with Epic DoT, Pox, Bane, JBB, etc.

But I agree if you do need CoTH, dropping the Shaman would probably be the right move, since Mage can take over the Malo duty.

Well with 2 ench, you have slow covered and you don't strictly need it because, you have 2 charmed pets doing the tanking. Consequently, the buffs don't matter because the pets are tanking. You'd literally be there to Malo and back up heal.

Meanwhile, with 2 charmed pets, you need a way to handle breaks. A beefy mage pet handily takes care of that. A shaman can, uh, root if you have room. Your wolf pet is not tanking a mob and a hasted pet for very long. Not a great value add. Mage/Ench/Cleric has been the meta for some time now because of this.

The main thing it comes down to is mana usage. Shamans self recover mana much faster, so the Enchanters and Cleric only need to do what is required. A Shaman slowing would be better because then Enchanters don't have to cast it at all. Same with healing, you only need to CH in some cases. Otherwise Torpor works fine. This saves a ton of mana if you are constantly killing. This is because a Torpor Shaman will recover that mana much faster than an Enchanter or Cleric, even with Clarity. As I showed in the video, the wolf pet is very capable of tanking. It has 2000hp. You can also Torpor it, which helps make up for it's lower HP than an Earth pet. Shaman can give the pet FoS too, which would be an extra 400 HP.

The question OP hasn't answered is what level range. I agree Mage/Ench/Cleric is better at lower levels, because a Shaman wouldn't have Torpor. But at 60 Mage loses the edge, unless you need CoTH.

Showing your pet can tank 1 slowed cliff golem does not mean it can tank 1 slowed cliff golem + a hasted pet or two.

Once again, you don't need to slow everything because you have 2 charmed pets (and a mage pet) putting out insane DPS.

Back up heals are cool, I'll give you that. Mage rods are also super useful when mana gets tight.

Slow helps reduces how often you need to heal your Charmed pets, and it reduces the chance of your party dying when shit hits the fan. With a Torpor Shaman you can slow more often because you can just recover that mana really fast. You slow less without a Shaman because you want to conserve mana. Shamans also have an AoE slow for when shit hits the fan.

Mod rods are indeed great, but if you don't need to cast spells at all due to having a Shaman, that will save you more mana, especially since Mod Rods reduce the Mage's mana, which has to be recovered too.

Shaman pet + Shaman DoTs deal good damage too, so it isn't like a Mage is putting out way more DPS. They are still mostly a single target DPS toon, like Shamans.

Again, Shaman pet is pretty tanky. 2400 HP (with FoS) and Torpor is no slouch when it comes to off-tanking.

But as I said before, level range matters. I agree Mage is better before 60.