So something I've noticed about leading PVP groups is that if you go down, you're usually the priority to be picked up. This happens whether you ask it or not and can be a boon if you're the healer. At the same time, other players usually melt if they have a full group focusing on them. SO why not combine these two concepts to create a badass group leader that can keep their team on their feet and make it really easy for your team to pick out one person to beat down? At the same time, we want to have some survivability so that our team doesn't wipe because they're trying to get us. Credit goes to one of my friends (he'll know who he is once I share this :) You rock for giving me evil ideas for the armor setup)

What do our sets look like, you may ask. The Trolliest ever, I respond.
Monster set: Troll King, both pieces. +2% heal is great, but the 2nd effect is what will make us a truly superb healer while still staying up: "When you heal a friendly target, if they are still below 60% Health, their Health Recovery is increased by 1548 for 10 seconds." Think about that for a second. If your heals tick on someone whose health is below 60%, fairly common in Cyrodiil, their health recovery is increased drastically. This applies to you, too, and meshes well with our main heavy set.
Full Set: Juggernaut. This has a pretty nice 5 item bonus: "When you take damage while under 30% Health, heal for 18060. This effect can occur once every 1 minute." So if your enemies figure out who's healing your squad, this will provide a HUGE heal if they get you low. Not only that, but if your health is high enough (via glyphs and item bonuses) this could end up activating your Troll King set. That's just not fair to try and fight against, and makes you tanky as hell.
Partial Sets: So, we're left with 4 more item slots, and for this, we're going to go with more tankiness. Bastion of the Heartland gives us more health, healing received, and reduces the damage we take from other players. It's one of my favorites, I'll admit. Akaviri Dragonguard is a good one while you don't have the full BOTH (also my favorite acronym lol) giving us magicka recovery, health, and healing received.
What about before you hit 50CR160? There's a nifty little set called Whitestrake's Retribution. Max Health, Health Recovery, and Spell Resistance is great, but it's 5 piece bonus is pretty similar to Juggernaut. Instead of actual health, however, it gives us a damage shield. Not quite as good, but it can happen every 15 seconds, as opposed to 1 minute. If you can find someone to craft it all in training (and there's no reason why you can't, srsly, most good PvP guilds have crafters who'll do it for the materials only) even better. We want to level as fast as possible, and as fun as non-vet PvP can be, Troll King <3.

On to the fun part: Our skill bars.
Bar 1: Focus on the glowing one!
Destro Staff: Lightning. There's some passives on the Destruction tree that increase the effectiveness of our AOEs, we may only have 2, but there's only 1 direct single damage attack we use, and I have to admit I just like the Lightning heavy attack better than the Flame heavy attack, which would be our second choice.
Piercing Mark: This will make it easier for your team to focus down one enemy, and is also great against Nightblades since it helps you find them even if they try to stealth. That would be great by itself, but it also lowers their resistances and heals you for 40% if the target dies, so there's no downside.
Pulsar: A tidy little AOE, with an extra special "Oh Shit!" for your enemies; it lowers their max health for 30 seconds. Combine that with Piercing Mark and your enemies will vanish.
Funnel Health: Such an easy one to spam, drops a nice little HoT on you and one member of your squad. Straightforward, keeps your team up and can activate Troll King.
Sap Essence: Another goldie from the Siphoning tree, ups your spell damage if you hit even one enemy, but really shines vs zergs. Pops a heal for you and your allies that increases for every enemy you hit with it and is a decent sized AOE on top of that.
Dark Shades: Why have one leader when you can have 3? Your two shades not only damage enemies, they also reduce the damage your enemies do by 15%. 4 seconds might not seem like a long time, but it can seem like forever when 10 or more people are melting your health. You can swap this out for Impale if you want a little extra DPS against low health enemies, or prefer a flame staff to a lightning staff.
Ult: Sturdy Horn: War Horn is great as is (+10% to all resources, everyone should run with this if they can), but throw in added time and extra resistances and it can make all the difference in taking a keep. Hopefully, you have several people with this on their bar so you can stagger it out, but if not, you should be able to pop it pretty frequently anyway (at least once or twice a siege, when rushing a breach or when a breach is getting rushed)
Bar 2: Let’s stick together
Restoration Staff: You're a healer. This is how you heal, but I'd think that goes without saying :)
Blessing of Restoration: A burst heal, albeit a minor one, but it hits a large area and increases everyone's resistances. If  your group is running tight, you can hit even a large group pretty easily with only one or two casts.
Efficient Purge: Purge is expensive, but it's our only real way to get rid of negative effects on our team. Efficient Purge lowers the cost by about 1/3rd. You can swap in the other morph if you want some extra healing, but Troll King should take care of that for you.
Illustrious Healing: An AOE Heal, great for rushing/defending a breach, and another way for Troll King to proc. It's relatively cheap while covering a pretty large area.
Dark Cloak: When things get too hot, this helps you duck out to fight another day. Other uses: Burning a forward camp, ambushing at gates, surprising enemy forces when you arrive just too late to stop them from starting to flip flags, AND SO MUCH MORE. While sweeping for people hiding in a keep, this can be swapped out for Radiant Magelight. Anyone who's spent even a little bit of time in PvP should know how useful this is, but for those who aren't familiar with what stealthed enemies can do: two Nightblades and 6 ballista can drop a wall from inside a keep in only a couple minutes, and be a pain in the ass for defenders IF they manage to show up on time. You'll want someone to have this as one of their skills in any group, so it might as well be you.
Mutagen: A cheap HoT that gives a burst heal when someone falls too low on health while taking off a harmful effect. That might not sound like much, but if your buddy who insisted on bringing a vampire to PvP catches fire, that'll remove the fire and heal his goth butt enough for you to swoop in with some real heals. (And Troll King ftw)
Ult: Soul Siphon: Take a great skill for damage, take away the damage and add super heals to you and your allies AND make you and your allies take more healing makes this one of your best burst heals. It's cheap to cast and can make all the difference when you're getting swarmed.

So, how do our skills all fit together?
As a leader, communication is key. Piercing Mark gives a visual aid to your team, to help them know who to go for next, Pulsar and Dark Shades will do passive damage to your enemies’ effectiveness, while Sap Essence and Funnel Health will keep your own forces up. The way I’d fire them off goes: Dark Shades (lasts 15 seconds, gives you some passive DPS) Sap Essence (increase your spell power) Piercing Mark (signal your team) Pulsar (lowers enemy health, plus DPS) Funnel Health (HoT, especially useful if we have high critical chance) If we forwent Dark Shades, hit Impale once your target is below 25% health for an almost instant kill. Weave in Light and Heavy attacks for extra damage and to restore magicka as needed, rinse and repeat as needed.
Our second bar comes up more defense than anything else. You’ll want Mutagen to be up pretty much all the time, Blessing of Restoration helps if your team is getting too low on health and can hit a large portion of your group if you’re good, Illustrious Healing can be thrown down where most of your team is standing, and can proc Troll King if anyone runs into trouble, Purge comes in handy if you’re getting hit by siege or any kind of DoT. Dark Cloak doesn’t need any more explanation, I think, nor does Radiant Magelight.
Our Ults have different purposes: War Horn is good to pop before anyone needs heavy healing, Soul Siphon is heavy healing. Pop War Horn as you run into a group, hit Soul Siphon as you’re fighting to keep people from going down. Easy enough to remember, I think :)