An item with higher item level will have more stamina, armor and secondary stats. The only drawback is the lack of strength, but that is not a main stat for us so does not really matter. An item with haste spirit int is probably better than an item with hit dodge strength if it is higher item level.
One of the intellect items I used was the 502 boots from Stone Guards HC which I got the second week. As we did not have a hpala I was the only one to get the item. At this point I only had 463 boots. The boots from sha of fear did not drop yet at this point, they were not added. But hey, lets for your benefit pretend like the sha of fear boots was already added.
So now we are comparing.
Heavenly Jade Boots
3867 Armor
+1441 Stamina
+881 Intellect
+546 Critical Strike (0.91% @ L90)
+630 Haste (1.48% @ L90)
Yellow Socket
Socket Bonus: +60 Haste
Reforge = 218 points, so given that, you get 630+218+320+60 = 1228 useful secondary stat from the boots.
Angerforged Stompers
3,547 Armor
+754 Strength
+1,131 Stamina
+573 Haste
+382 Mastery
So basically. The difference between the boots:
Int boots: +1320 armor
+310 stamina
+881 int ( hey, still gives spell crit, not entirely useless even though horrible )
+328 crit ( as above, not entirely useless )
+273 Useful secondary stats
Strength boots: +754 strength
So you tell me? Which is better
1320 armor, 310 stamina, 881 int, 328 crit, 273 useful secondary stat vs 754 strength. Not even a bloody question for me.
Same goes for like belt, if you are using a blue belt, there are epic belts with 2 sockets, those 2 sockets alone are 640 secondary stats.
In not all cases but almost all cases, higher item level = better, even if it is int. Ofc if the stats are useful.
Like, you wouldn't take a spirit crit int item probably. However an int 489 int item with say haste spirit is probably better than a 463 strength item with hit/exp/mastery and dodge/parry.
Feel free to compare more items yourself, really cba to do it myself since I would just prove my point over and over again.