I would like to say that Crusader is suited to a very specific play style. Think of yourself as a very slow Incredible Hulk. You don't hit fast or often, but when you do it hurts like hell. Below you'll find my build which has been working pretty well up to and including Torment I and most, not all, packs in Torment II. Being the first day of the expansion I must say that I'm quite satisfied with this class and have been enjoying it much.
Left Click: Slash / Crush.
Simple. This ability crits all the time. It splashes damage reasonably well and does plenty of single target damage to for a resource builder.
**I've been experimenting more and more with Slash / Zeal. This seems core if you're running a two hander and greatly increases the amount of Wrath that you are able to generate.
Right Click: Fist of the Heavens / Retribution
This ability does plenty of single target and AOE damage. Not only will it trash things single target but it will clear packs with ease. This is by far my favorite spender.
**Sweep Attack / Blazing Sweep is currently appearing to be the best damage per Wrath for the Crusader. I've changed to Sweep Attack for the time being, but with enough First of Heaven's damage on gear, FoH may still be ahead and is better for area clearing unless the mobs are very, very stacked.
1: Condemn / Unleashed
This ability does MASSIVE area damage. I've seen over 12M crits with this. If you're soloing, using Eternal Retaliation is probably better, however in groups usually the charge up causes you to miss the damage and therefor make it useless.
2: Judgement / Resolved
Couple this with Condemn and you're in for a good time. This will root your enemies and cause them to be crit 80% of the time. Literally pushing most characters to over 100% crit.
**I like this ability personally though I've been criticized for using it. This ability would be the simplest to switch out for something you prefer. If you want massive damage, Bombardment, Steed Charge (for times you need to GTFO), Provoke, Falling Sword and Heaven's Fury are all good choices. Let me know what you think!!!
3: Laws of Valor / Critical
Laws are simply too good not to use especially if you're using a two handed weapon. This ability will make it feel more like a one hander and also combined with 2/1 = massive numbers.
4: Iron Skin / Reflective Skin
Simple. Turn this on and stand in something. Watch the elite pack melt. GG. This ability also breaks freezing and other CC abilities such as jailer.
**I've been using Akarat's Champion / Rally more and more lately in place of Iron Skin. My Thorns damage recently took a hit and the CDR on my other abilities with Akarat's Champion really allows me to melt elite packs.
Passives are tricky mainly because they greatly depend on what you're using for weapons. Currently, I am running the following:
Wrathful - This will allow you to heal for massive amounts when you spend your wrath. This is incredibly necessary for living in higher difficulties.
Righteousness - Simple. More wrath generation is more healing and more damage. What is not to like?
Fervor - Amazing. 10% IAS is exactly what you need. This class feels incredible IAS and CDR dependant. I believe that stacking IAS/CDR with a medium amount of Crit and Crit Hit damage will give you great damage and survivability.
Heavenly Strength - Lets me use my new Skorn. Worth the movespeed penalty for the damage that comes with my new weapon.
For living better you can always replace Fervor and Righteousness with something like Hold Your Ground and Renewal. Other talents not to be overlooked is Iron Maiden, Finery and Long Arm of the Law. These abilities are amazing. Indestructible appears to have a place as well, however I haven't messed with it yet. It's very easy to make yourself tanky enough to survive anything, the trick is to not sacrifice too much damage. Finding the sweet middle ground between Healing/Toughness/Damage is difficult and character specific.
Bottom line is, I don't think that you should sacrifice the passive slot for a 2 handed weapon unless it's really, really worth it. Let me know what you think! Please be constructive, that is my only request.