Stealth in this game is [censored] with perks which allow you to crouch during combat and somehow disappear.
Except it doesn't. The final stealth perk does jack all in my experience.
Stealth only become ridiculous after I got multiple bits of +40% stealth armor enchanted at 100 stealth with all perks. Before that it was perfectly fine. And when you have perfect gear and max skills and perks...well it should be extremely powerful.
And even with +200% stealth at 100 stealth skill, there are plenty of enemies that detect me if I walk in front of them.
Of course nothing detects you if you are using Invis...but that has nothing to do with stealth.