Primary stat, critical hit chance/damage (1/10 ratio), and CDR (depending on builds) are the most important stats I should look for for most builds, right? I don’t want to get too hardcore, I just want a good starting rule that applies to all classes and builds.
Do pets benefit from CHD? I read that they have a flat +50% CHD and cannot benefit further, but these posts are like 6 years old.
Generally speaking, this may be so. As you stated, it depends on the build. For example, some builds may have a higher priority to Area Damage.
If you look at build guides on Icy Veins (check the Gear, Gems & Paragon Points page) or DiabloFans they will list the priority of item Properties in order. On Icy Veins they are numbered 1 through 5 (or 6). On DiabloFans they are simply listed in order of priority. (Or they should be. It depends on the build guide creator).
For clarification: You have that backwards. The way you’ve written it, that should be critical hit chance/damage (10/1 ratio) or critical hit damage/chance (1/10 ratio). For every 1% of Critical Hit Chance you want 10% of Critical Hit Damage.
If you have 50% CHC you should have in the neighborhood of 500% CHD.
I would say no. But, I’m not sure. I do know that some Classes have Skills (with certain Runes) and Passive Skills that will increase Pet Damage, Toughness and Attack Speed. There are also items that can benefit Pets. Like Tasker and Theo, which can be equipped or cubed by any Class and boosts Pets’ Attack Speed.
Perhaps other players, with more knowledge of game mechanics, can offer more information.
If pets didn’t benefit from CHD, then why do all (non-thorns) pet builds stack CHD, have an emerald in their weapons and so forth?
It may be possible however that the pet damage is calculated differently and they do somewhat constant damage based on the amount of CHC and CHD you have. Maybe it’s a similar case like DoTs which essentially don’t crit but their damage output is scaled on CHC&CHD. I don’t know the inner workings of damage calculations of certain things.
Is it true that followers (Enchantress, Templar, Scoundrel) are also considered as pets?
I thought, pets are like DH’s Companion, WD’s Zombie Dogs, Monk’s Mystic Ally, and Necro’s Golem, etc (I wish Wizard’s Hydras could also be considered as pets).
Followers aren’t pets.
Hydras are pets.
YES! Thank you, thank you, thank you 
I’ve been looking for this answer for 3 days.
That’s why Enforcer gem is used in Hydra builds.
I believe the Demon Hunter’s Sentry is considered a Pet too. I know they are affected by Tasker and Theo.
Sentries are pets too.
But M6 build uses them to buff player’s attack. They are not the major damage dealer.
