In a game with this many attributes, numbers and mechanics, it is hard to find a single source for information on what constitutes a viable build.
I have several hundred hours of game play, and probably as much if not more spent in Grim Tools. I give up on most builds somewhere through the process, because I keep on running into a new piece of information that seems to be a “viability” rule that I missed.
I have also spent a lot of time looking at the build compendium and in many ways that gave me more questions than answers. I am either to stupid or lazy to become a theory crafter, maybe a bit of both.
So here are my questions:
Offensive Ability
It seems to have an absolute minimum of 2500, with more being better. If I understand correctly, more will give me more crits. Is 2500 enough to always hit, and should I over cater for debuffs? By how much? Is it necessary at all for retaliation builds (which I also read is not viable)? Is it possible to stack OA at the cost of DA, where kill speed will exceed the need for strong defense?
Defense Ability
Also seems that it should at least be at about 2500, with some above 3000. At which numbers does bosses start missing you 40% of the time? Where will they never crit you? If you use a shield is the block mechanics strong enough that you can skimp on DA?
Resistances
Here it seems max it out is the rule. Does going over the limit help with resistance reducing debuffs at all? What is the minimum required physical resistance? Does it differ for ranged/caster and melee? Can you have more health and less resistance and still survive? Once again, does having a shield have any effect?
Armor and Absorption
Obviously more is better, but does high physical resist mitigate the need? Does more health mean you need less? Shields again? Ranged vs melee?
Health and Health Mechanics
Here the magic number my searches found seemed to be 15K. Why I do not know. How strong is health regen? Can a high life steal mitigate low health pools, or can any of the above defensive mechanics allow you to have a lower health pool?
Crowd Control
Will having strong crowd control mitigate the need for any of the defensive stats, or is it just nor strong enough? Does it even work on bosses, because it seems most don’t?
Damage
Seems straight forward - more is better. I am not going to try and decipher how abilities, % boosts, flat damage and all other moving parts works together, but is a highly focused damage type (or 2) build the only viable solution? Is there is a certain point where dps is just so low that a boss will take an hour, or infinity, to kill? Is there a point where you hit so hard that you have to compensate in other ways for reflective bosses? Except for a couple of niche shaman builds, are two handed weapons really that bad?
Sets and Viability
The one thing that surprised me most when checking the build compendium, was that not many builds are centered around full sets. Are set bonuses that weak? Or is it just nigh impossible to get all the above requirements covered when using a full set? Are you forced to farm MI greens with perfect pre- and suffixes to get the stats you need?
Also, what does viable mean? Seems 170 gladiator is the measure? Why? Is it the absolute limit you can achieve?
Well that’s the lot, I think? (I will skip the interaction of pets on all of the above for now :o) Although it is fun to fidget in Grim Tools, and entertaining to search the forums and reddit for answers (no matter how varied the opinions), I would rather just be enjoying the game.
If you waded through this wall of text, thanks in advance.

Few other posters have shown that Infernal Knight or Blood Knight are good too. Then other sets like Justice have always been amazing.
