That's alot of armor but pretty poor resistance. What if you change Thornmail with Force of Nature, so you get more resistance and good HP regen? It also give you a little bost to movement speed.
Another thing: strength of spirit in mastery tree? for a hero who have no mana? What if you put 3 armor, 1 resistance, 4 evasion and 1 harden skin? or 3 resistance and 2 evasion, whatever.
You may also think to change the sunfire cape with Atma's Impaler since your w skill is enough to help you farming and since you have armor pen runes the extra phisical damage will do more then the fire cape, or (fun thing) rylai's scepter or the frozen mallet, both items that give you good hp and the better thing, slow the escaping enemy even more.