DPS Zealot
Is terrible. However, if/when T4 happens bombing Zealots are very viable in premade groups. Stack crit, take the heal debuff tactic and reduce the incoming heals of anyone you crit (with the DoT, PBAoE, Chaotic Agitation, etc) by 50%. For solo work or even 6-mans I would avoid a bomb Zealot though and in warbands you only need 1 (and expect to also heal).
Spamming Group Heals
Do you know what triggers from group heals? Blessing of Chaos, Restorative Burst, the bubble tactic, etc. Unless you
really need 100% maximum healing and have LOS, casual group heals are your friend. It keeps everyone buffed up so when they get focused they already have a bubble and incoming healing bonus applied to them.
Flash of Chaos is good if you're being focused or need mobility. If not, then group heals are by far the most effective way of getting your on-direct-heal buffs up on as many people as possible.
Warping the Spirit
This tactic becomes less and less viable as the ranks go up. Even though it's a tactic is doesn't stack with other armour buffs so high-level potions almost equal it. In T3 it's good but not silly broken. It also doesn't do much to help a Zealot or Shammy stay alive as between armour debuffs and penetration most/all of their armour is bypassed anyway even with talismans.
In addition, it does nothing to help with getting bombed by Bright Wizards or having a million DoTs on you from BW/Engi/etc.
Wind of Insanity: crap in RvR as you die in 2 seconds if you get looked at but it's borderline broken in scenarios. Remember it is NOT a channelled ability - you can keep casting other things during the time it is active. If your group gets rushed, turn this on and start spamming heals - the enemy will be punted away and you have enough time to get everyone back to full health. It also gives you good objective/flag control in scenarios as well - in Tor Anroc it allows you to dominate the middle of the map. It also allows you to dislodge def-tard tanks holding on to the middle point in Gates of Ekrund.
It also locks down spellcasters - Archmages, Bright Wizards, are all prevented from casting spells with a cast time as they keep getting knocked-back and interupted.
Oh, it also completely destroys magnet attempts. Get pulled in, turn on for 2 ticks, turn off and run away. I've used it to avoid/counter them in both RvR and scenarios - as the CD is shorter than Electromagnet if facing just one Engineer then you always have a counter on hand.
Spec
I am currently using this:
http://waronlinebuilder.org/#career=zea ... 720:5721:0:
Wind of Insanity: see above
Bubble Tactic: good against all kinds of damage, can be pre-applied via group heals, has no internal cooldown
Chaotic Agitation: this is a renown cannon (disclaimer: not tested since the devs started changing how renown gets handed out). In addition, it's a great tool for farming NPCs. If you see a group get Rifted in front of you then target the nearest enemy and use this ability to add to the damage.
Ritual of Lunacy: This is basically a group HoT for the Zealot.
Morales
The Zealot has what I believe is the highest armour/resistance buff and debuffs in the game on it's morales. Unfortunately they compete with Divine Favour and Focused Mind.
M1: Tzeentch's Talon - huge single-target armour and resistance debuff.
M2: Eye of Sheerian - huge group armour and resistance buff.
If EoS was a M3 instead of M2 it would likely see a lot of play (the M3 group bubble is great for pre-healing but doesn't give any increase in attrition - when the bubble is gone that's it).
Oh, and never forget the M3 - a 7 second PBAoE silence called Suppressing The Fragile Unbelievers (STFU).