Sorry for the clickbait title. My last post was too broad for explicit discussions, and templars need it the most. I'm going to run through skills, perks, gear, and some other buffs for the class, while highlighting the weakest abilities in the class trees and perhaps the weakest in the game.
Generally speaking, templars have the hardest time dishing out competitive dps in PvP because most of their abilities are channeled or have an extended cast time. Also, since I haven't been playing since beta, I've heard that some of the abilities were nerfed much harder than they should've been, so my opinion isn't really shaped by what the class used to be. From what I've seen so far, templars have a harder time at stacking spell power, as opposed to sorcs who have built in passives for spell power. While running a 5 set of julianos, molag kena, and torug's pact dw, I have just over 2k spell power and around 2k regen (with drinks). This is average at best, and I wouldn't have too many complaints if templar abilities could actually back up the stats.
Aedric Spear tree
This tree is more helpful to stamina classes than magicka, even though magicka templars rely on these skills as more of a crutch.Puncturing sweep would be an amazing ability if it didn't take 2 seconds to channel. The self heal is nice, especially if your single target dps is at 10k or higher, but for the most part it can be easily countered or interrupted.
Piercing Javelin is completely useless and a minor inconvenience to other players at best; it hardly does any decent damage and is only useful if you're knocking someone off a wall to their death.
Toppling Charge (Focused charge morph)-
This deserves some serious focus because I have several problems with this ability. It is by far the worst gap closer in the game whenever it doesn't bug out completely and make your character glitch in place as it fails to function. The charge animation takes so long to finish that your opponent can break CC before you can even set off one of your channeled abilities. I tried running 1h and shield with shield charge since it's a much cleaner animation and a more reliable gap closer, but as a magicka class this is incredibly inconvenient. If anything, the actual bug in this ability needs to be fixed. I've found it to occur most often when your target isn't on the same ground level as you are.
Spear shards is a bad AoE, acts like a no-scope CC that doesn't do much damage, and is only useful for trying to find stealthed players. The only reason it'd be used would be for a group with stamina builds who can synergize off the shards, which is why templars are a better class for PvE dungeon runs. There's a reason why you see this ability spammed, it's a less annoying version of Ambush because it will take hours to kill you.
Sun shield is just awful, I've replaced it with Harness Magicka. If Blazing shield had a longer duration, it might be worth using, but scaling off of max health can be either somewhat helpful or completely pointless. I'm a templar, I sit at 18k health because I have 18 different self heals to choose from, so why do I have a ward that only lasts until one of my channeled abilities is done then dissipates while stealing my resources? Lengthening the duration will not make templars OP, it will just take into account that every templar ability takes forever to cast, and casting blazing shield between each ability just makes it useless.
Radial sweep is decent, I don't run it because there are better AoE's I can run, especially if I'm focused on ranged attacks (definitely not nova though).
Dawn's Wrath
Sun fire (Reflective light & Vampire's bane): Reflective light is still bugged, as in it should hit up to 3 targets in front of you, unlesss they're at varying ranges, then it might hit 1 or 2 at best. Vampire's bane doesn't do enough damage and the snare isn't effective enough to even run, plus the bonus to crit is marginal at best. Again, I'm a templar, my spell crit is at 50% because critical heals save lives, so running Vampires bane to get my spell crit 10% higher for a few seconds makes a hardly noticeable difference to gameplay, if any.
Solar Flare: Solar barrage makes sense if you're a hybrid magicka tank in the middle of a group of enemy players. Dark flare, however, is the infamous holy flaming beach ball that floats towards its target, and is without a doubt the easiest attack to dodge. Whoever made that arched travel path seriously didn't want it used in PvP.
Backlash: ....meh.
Eclipse (Total Dark): Only works on magicka builds, only problem with it is not being effective against inevitable det or sorc's curse. Also not a reliable self heal.
Radiant Destruction (Oppression): Even though it's a channel, and I hate channels, it's actually one of the most reliable executes in the game, given you have line of sight and know when to use it. I've seen lots of templars take note of the large damage output, not take into account the channel time, and use it on shield stacking sorcs with 100% health. PLEASE DON'T DO THIS. You will make the sorc laugh his face off before you even cut through half of his wards. Also, even though the ability triggers extra damage below 50%, don't use it until your target's around 20%. This will guarantee an execute and not keep you stuck in a channel while your target has time to crit rush or CC you and break the channel. Again, this is probably the best dps ability that templars have going for them, but it's abused so often it makes me want to cry a holy tear.
Nova: great for PvE.
Restoring Light
This entire skill tree is the reason templars are targeted first in a group. If you're running around spamming breath of life or healing ritual, you will get knocked down immediately and beaten to death. Healing ritual is a hard animation to cancel, but it's a little easier with breath of life, the key is to not spam it. If you're in a gorup and people are close to death, the best option is to pop a healing ward then follow it up with a subtle breath of life to ensure everyone stays up.
Repentence: the other morph isn't even worth mentioning because nobody uses it. This is a great no-cost heal and stam return, but I've found it to be more useful on stamina templars than magicka. However, if you're in a group, it's a great ability.
Purifying Ritual: I love this ability for many reasons. It cleanses DoTs, mark, snares, etc, and is much cheaper than purge. Please keep this ability as is.
Rune Focus: This ability would be more useful if the rune had a larger diameter. It almost enourages the lack of mobility in templars by restricting them to a tiny disk the size of the smallest enemy AoE. Since it's low cost and has an 8 second duration after you leave the rune, it's decent, however a larger rune would be nice. That's just my personal preference though.
To sum up, Magicka Templars have a very hard time at being competitive in PvP whenever they're not in a group. I've seen some builds that use the bow passives for mobility as well as some medium armor perks, but this is highly inconvenient if you're swapping out a resto for a bow on your support bar, as well as losing certain passives when using medium armor. Since I run dual wield, I could run quick cloak for the major expedition, but that'd cut into my very small stamina reserve so I'm less inclined toward it.
Here's my build
Gear: 5 Julianos (divines), 1 Molag Kena (heavy, divines), 4 Torug's Pact (1 body, 2 swords w precise, 1 resto w precise), 2 magic regen jewelry and 1 spell power.
Mundus is Atronach for magic regen
Bar 1 (dw): Puncturing Sweep, Radiant Oppression, Toppling Charge, Dark Flare, Harness Magicka, Dawnbreaker as Ult
Bar 2 (Resto): Repentence, Purifying Ritual, Healing Ward, Breath of Life, Channeled Focus, Ice Comet as Ult
If you have any build suggestions or other opinions on abilities, feel free to comment.