There are a couple of useful combo's for the paladin, which are
The defiant: a defence based paladin, but since you need a lot of extraordinary good items to achieve high armor, I think it isn't a very good choice. Still think the same.
Thorns/conversion: Great combo but quite hard since your conversion rate is quite low and your minions might turn on you when the conversion time is up. Conversion is greatly nerfed in duration so pretty useless.
Holy freeze: this is based on flashing skills, battle.net works with pulses, you can change aura every 3 seconds but it will be changed every 8, this means you can have both a damaging and a holy freeze aura for 5 seconds, very hard to control, especially with not so experienced players, so not a very good choice. Still thinking the same about it.
Fanaticism/zeal: This combo is VERY equipment intense, because you need these items: iceblink, the (25% crushing blow shoes) goblin toe I thought, golwrap, sias gloves, and a very very very fast weapon, fast attack speed +gias is recommend or very fast attack speed +ias, so not a very good choice. Fanaticism now does damage making it very attractive but still pretty equipment intense.
Blessed hammer/concentration/charge: I think this is the kind of combo we are looking for, with concentration hammers do about 500 dam each and you can fill your mana and kill bosses with charge, and you can hold shift and charge in a crowd and out, in, out, in, out. 500 damage in the xpack is low, because monsters will have 5000-10000 hitpoints so I think we should forget this one.
Conviction/vengeance: This skill-combo will be great in the x-pack because of the lower resist of conviction and higher vengeance dam, If you party up the melee characters will love the - defence from conviction and sorceress will like -resist because she will dish out huge damage.