D&D 5E Amulet of Health, Another Strong Item

[KarinsDad]

It's not arbitrary at all; it's based on the item's general utility. Given the choice between a wand of magic detection, goggles of night, and gauntlets of ogre power, I can see a reasonable party choosing any of the three (well, okay, the goggles would probably win out most of the time, but not by a lot).

Add an amulet of health to the list, and it becomes a no-brainer for 99% of parties. You can have free magic detection; you can have 60-foot darkvision for one PC;

You might be overestimating how strong 60 foot darkvision is in 5E.

If foes are just milling around, sure, they are seen, just like in earlier editions.

If they are hiding, Darkvision is like dim light. Dim light (i.e. lightly obscured) is at disadvantage to perceive hidden foes. Chances of spotting a hidden foe in earlier editions was perception vs. stealth. In 5E, disadvantaged perception vs. stealth.