I am doing 3Warriors+2Paladins and it has been slow going at times. It seemed to pick up at 13+ when I found the Defias HyperSpawn by the Windmill. Things also improved greatly at Level 20 as Cleave helps with multiple target DPS & 'Flash of Light' really helped with Healing. I also helped that I spent some time on my ISboxer setups and some in game macros. I anticipate that Level 30 should be a Watershed moment on Healing and 36+ should be where DPS really starts to take off.
There have definitely been times when 1 healers output was not enough for the spike damage and there also have been times where one healer would have gone OOM so I think 2 healers work well at the lower levels for the way I play at least. I am also glad to have 2 rezzers...
PVEwise Paladins are the most efficient healers (post level 29) due to Illumination and all things being equal should require the least amount of drinking for a Warrior team (especially when they also have Seal of Light at 30+ & Seal of Wisdom at 38+). The exception would maybe be a Warrior team feeding killing blows to a wanding Priest but I personally would not want to manage all that (I just want to grind fast) and regardless a Priest doesn't fit my goals (my brother and I both want to main a Paladin like we did in Vanilla so we need 2).
Generally at cap and geared with at least pre-raid BiS gear 4Warriors+Healer should be one of the best PVE Dungeon Grinding teams.
4Warriors+Shaman with Windfury will likely be the best DPS for much (if not all) of the phases though in the later phases Blessing of Kings on a Paladin+4Warrior team will scale really well and with top notch gear may be on par or better.
3Warriors+2 Paladins is certainly less DPS overall but isn't as far behind as it may seem as you get a second Blessing, Aura, & Seal from the 2nd Paladin and the Paladin is also doing damage (though less).
In my case 3W+2P made the most sense because we want 2 Paladin mains and because 2 healer are much better in WPVP (which is more important to me than PVE Dungeon Grinding).
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