Elise Build

So I am currently playing a ton Elise because shes my favourite champion and would like some critique on this build that I've been using.

Runes: Magic Pen Quints/Marks, 4flat Health Seals, 5flat Armor Seals, 4scaling magic resist glyphs, 5scaling magic resist glyps Masteries are 16/14/0: Offense: Double Edged Sword, Fury, Mental Force, Arcane Mastery, Archmage, Executioner, Dangerous Game Defense: Block, Unyielding, Enchanted Armor, Veteran's Scars, Juggernaut, Swiftness, Reinforced Armor

Usual build order is: lastly or

This build puts me at 44magic penetration(potentially 64 with abyssal scepter) which I really think is cool but currently I find myself dieing to adcs everywhere even when I reach that 170+ armor I believe its because Elise's health pool is pretty small. Anyways I really like this build because it gives me so much magic penetration, 40% cool down reduction, able to constantly proc full liandries but I'm having trouble with staying alive in late game fights, I know Elise is like a early game champion but I kinda like surviving lol. Anyways please critique build and things I could improve, change, change throughout the game like sell some stuff if it gets late game and maybe add play styles as well, I wanna become a better Elise playaa.

Edit: Also I usually have to go randuins right after liandries because the adc starts hurtin