Instead of 2 Paladin's healing did you ever try converting one Paladin to Tank and dish out DPS and then have one of the Paladin's keep Seal of Light up on the enemy?
If your Warriors were running dual Crusader Enchants on something like FlurryAxe+ThrashBlade with HandOfJustice (or IronFoe instead of FlurryAxe) I would think they should be getting lots of little Healing from both Crusader Enchants and the Seal of Light's Judgement.
Hopefully that kind of setup would help smooth things out well for one healer to generally manage and the DPSing Tank Paladin can still be a periodic off Healer to supplement the healing of any spikes. If that ends up being too mana intensive you could try to weave in Judging Seal of Wisdom so hits on the target help refill both health and mana for the Paladin(s).
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