I've seen an interesting thing that has been in Wow only since Legion, and I'm sharing it with you.
I used to twink in Mop, and back then, a difference of 100 ilvl between two items meant that the second item was approximately 2.7 times better, it means 2.7 times more stamina, 2.7 times more intellect, AND 2.7 times more secondary stats, as crit, haste and mastery.
But now it has changed, the secondary stats are inscreasing way more slowly.
Let's take and example : I look at Serrine's Maleficient Habit (Head cloth) at ilvl 835 and 845:
835 : 1692 stamina, 1128 intellect, 459 crit and 776 mastery,
845 : 1857 stamina, 1238 intellect, 476 crit and 805 mastery.
Conclusion ? stamina and intellect (primary stats) are inscreased by 9.75%, and crit and mastery (secondary stats) are increased by only 3.74%, almost 3 times less !!!
THIS is why I STRONGLY recommand you to take items with either socket or tertiary stat (leech or speed, because avoidance is pretty much useless). What makes a twink good isn't stamina nor intellect, it's secondary stats, if you want good stamina and intellect, level your character to 110, but if you want good secondary stats, let it at level 101. You can have 30 more ilvl on an item, it's only gonna give you like 100 more secondary stats, less than the 150 given by sockets, and far less than the +500 that we can get from having leech or speed on an item.
Look at my two twinks : Affliction Warlock 805 and Balance Druid 815, then don't have very good ilvl but almost every item has either a socket or leech / speed. My Balance Druid has 35% passive leech, and is almost unkillable thanks to that (unless by stuffed 110's).
Affliction Warlock :
http://eu.battle.net/wow/en/character/culte-de-la-rive-noire/Hykkram/simple
Balance Druid :
http://eu.battle.net/wow/en/character/culte-de-la-rive-noire/Winterleaf/simple
By the way feel free to add my Battletag Hykram#21796 , I'm on Alliance side and I like mainly WPVP and dungeons / raids. We can even go to AP farming ! =)