The most common mistake is not investing enough into damage. Damage is everything. Always.
Crit can be found on:
- Shields, up to 10%;
- Gloves, up to 10%;
- Amulets, up to 10%;
- Bracers, up to 6%;
- Helms, up to 6%;
- Rings, up to 6%.
Crit damage can be found on:
- Weapons, up to 100%, Emeralds socketed into weapons can give up to another 100%;
- Amulets, up to 65%;
- Gloves, up to 50%;
- Rings, up to 34%.
IAS can be found on:
- Weapons, up to 11%;
- Amulets, up to 9%;
- Gloves, up to 9%;
- Rings, up to 9%.
Since this question will arise for sure, I'll just say right away that crit > critdmg. Obviously the value of critdmg completely relies on the amount of crit you have, but there's another factor here and that's Cyclone procs. Crit chance will improve proc rate, crit damage will not, and Cyclone is a huge contributor to our damage now. Regardless of what spreadsheets will tell you, keep this in mind.
Rings are the last slots you should upgrade from IAS to crit/critdmg items, or not even upgrade them at all depending on your current rings and budget. They can carry much less crit than other slots, but the same standard amount of IAS. Also, items can potentially have all three of these stats. Just something to look forward to.
The best approach to defensive stats in this and nearly all similar games is balancing them out. Never tunnel one stat. It's not good to have very low hp but very high mitigation, just as it is not useful to have very high hp but very low mitigation. It's useless to have lots of LoH, but health pool so low that you're going to die every time you stop hitting. Also, you stop all damage when you kill things - don't focus too much on defense. You need just enough, not too much.
To answer two of the most common questions:
1) OWE works like this: if arcane resistance is your highest stat, and you get an item with +50 all resistances and +50 arcane resistances, the total gain from that item will be 100 resistances;
2) LoH procs from all direct damage. Damage auras and DoTs don't proc it, but all our AoE cleaves do, per target. If you hit a target with Fists of Thunder, and Thunderclap will hit your main target and another 5 offtargets, it will be: 1 hit from FoT, 1 hit on main target from TC, and another 5 offtarget hits from TC, total 7 LoH procs. However LoH is scaled per ability, check the table linked in appendix for exact values.
- Weapon: DPS, Life on Hit, Socket, Crit Damage, Weapon Type, Attack Speed, Dexterity, Life per Spirit Spent, Vitality
Weapon is the only slot that can carry high amounts of LoH. There's really no such thing as "LoH build", there's just "LoH weapon".
Attack speed on weapon is multiplied with total IAS on gear, so there's nothing bad about weapons with IAS contrary to popular belief. There's a difference in base attack speed depending on weapon type: Daggers (1.5) > Swords/Fists (1.4) > Axes (1.3) > Maces and Spears (1.2).
Only Fists and Daibos can have Life per Spirit Spent.
- Shield: Block Chance, Block Amount, Crit Chance, +% Block, Dexterity, Resistances, Vitality, Life %, Reduced Damage from Elites/Melee/Ranged
Pay attention to shield stats - block chance and amount - they make a big difference although it might not seem so on paper. Damage is blocked after it is reduced by armor and resistance, think about that. Picking a shield is like picking a weapon - block chance and value are main stats on it, like damage is on weapons.
- Amulet: Crit Chance, Crit Damage, Attack Speed, Life on Hit, Dexterity, Resistances, Vitality, Life %, Reduced Damage from Melee/Ranged
Amulets can actually have very considerable amounts of LoH, high end ones are around 600.
- Rings: Attack Speed, Crit Chance, Crit Damage, Life on Hit, Dexterity, Resistances, Vitality, Life %
I keep attack speed as highest priority here simply because you can find more of it than crit. Amount of LoH on rings is abysmal.
- Helm: Crit Chance, Socket, Dexterity, Resistances, Life per Spirit Spent, Vitality, Life %, Monk Skill Bonus
You want a socket to put an Amethyst there for 15% Life. I think this is pretty important, but completely viable to ignore it if you won't go below 30-35k HP or so.
There are some interesting choices here when it comes to class stats - you can get a 11% damage modifier to any primary skill. Don't overestimate this stat, it won't be better than 100 Dexterity. These and Life per Spirit Spent are available only on Spirit Stones.
- Belt: Dexterity, Resistances, Vitality
This would be just a standard armor slot if not for one item - slightly overhyped String of Ears. One of its predefined stats is melee damage reduction, up to 20%. However, it is a level 53 item so its stat rolls will be fairly low, and it has +11-20 resist to all as a set stat meaning it can't even roll for all resist. A good rolled item level 61+ belt will most likely be overall more EHP than String, even against melee (you can check yourself on the EHP calculator).
- Boots: Movement Speed, Dexterity, Resistances, Vitality, Life %
- Chest: Dexterity, Resistances, Vitality, Life %, Sockets (up to 3), Reduced Damage from Melee/Ranged/Elite
- Pants: Dexterity, Resistances, Vitality, Sockets (up to 2)
- Shoulders: Dexterity, Resistances, Vitality, Life %
Some notes about this list: order the stats are listed in can be treated as priority lists, but don't follow them to the letter. This game is about balancing stats and choosing what to prioritize depending on your own playstyle and which act you're at. There's no single pattern that will work just as good for every situation, think for yourself.
I skipped sockets on jewelry because if anything, that's a waste of a potentially better stat roll in my opinion.