Here's some basic knowledge of stats, and some of my thoughts on the stats imo:
Str
+Large Health Pool
+Quick Health Regeneration
+First Priority type stat for mirror images
-Slow Atk Speed
-Low physical resistance
-Low mana pool
Agi
+Outputs the most melee damage
+Large physical resistance
+Makes bash / maul (stun % on atk) more effective
-Low health pool
-Low mana pool
Int
+Quick mana regen
+Large mana pool makes good use for large costing, damaging abilities
+Extremely effective with mana shield (over 60 int)
+Mana shield cancels out life steal effects, and works with thorn aura (effective dmg return)
-Low health pool
-Low physical resistance
-Slow atk speed
Any constants below can be changed by map creator:
Stat Constants:
4000 arm = 100% damage reduction, can still be hurt by physical atks but not exactly noticeable, spells are not effected by this.
[?] 240-260 agi = max atk speed (0.01 cd)
1 str = 25 hp, 0.05 health regen+
1 agi = 1 dmg, 0.02 atk speed+
1 int = 15 mp, 0.05 mana regen+
Source: 3 yrs of playing enfos and hero wars
but on topic int is a very effective stat, its just you need to be watchful of your health pool and know when to use what ability. Agi imo is the best stat since getting a 4:1 (agi:str) char can be enough survivability with enough damage output.