I haven't played PoE that much so far, so I can't argue much about it. But I think Titan Quest has a similar attribute system:
Strength (Str) increases Physical Damage dealt (this type of damage is dealt by all weapons except staffs). It works on weapon base damage only. Strength is also a requirement to wear better warrior's gear.
Intelligence (Int) increases Elemental Damage (lightning, fire, cold) dealt. This includes regular weapon attacks (especially Staffs) as well as all attack skills dealing elemental damage and vitality damage. It has no effect on poison. Intelligence is also required to wear better magician's gear, like staffs and robes.
Dexterity (Dex) increases Offensive and Defensive Ability (OA/DA) as well as Pierce Damage, which is partially dealt by swords/daggers, spears, and bows. It is also required to use better types of these weapons and some other equipment.
Health (or Life, HP, Health/Hit Points) measures how much damage the hero can take before he/she dies.
Energy (or Mana) is required to use active skills like attack spells, summon skills, and auras.
But I guess regarding attributes there would be hundreds of possible examples. But linking attributes also to class choices is more unique to Titan Quest, I believe. While in Titan Quest you are limited to two classes, D:OS could go here even further.
Anyway I like the idea of the need to get into some kind of 'manaflow' or 'battleheat'. High level spells don't need more action points but need you to be in the correct mindset. So that you can't start a fight with a meteor rain wiping half of the enemies from the start. After fight of course it would reset to 0 and CC could set you back.
