On Herod I got my 3Warriors+2Paladins to 11+ and I created 3 5man groups of 4Locks+1ShadowPriest (each Priest on a different account so I could mix and match) and ran all 3 groups through the level 4 tunnel to the Inn to get their rested bonus accruing (it should max within 10 days).

I also maxed out my 50 character count on a few accounts reserving key names on every server just in case.

I had originally planned on running from my Healer main but instead I am running from my lead Warrior and loving it (especially once I got Charge on my Warriors). I finished setting up VFX in ISboxer so I can heal/buff/dispel on both healer accounts from my Warriors' game clients and really like how it is going so far.

I recommend you try running/driving your duo from both characters and contrast/compare to see what you like more.

As far as what character to add to your duo I would consider adding a Mage for free water/food/portals and to boost your team's DPS. Paladin DPS isn't stellar & though a healing paladin is very mana efficient a DPS/tank Paladin does need to drink...