I almost always get a Wit's End because it's very cheap to farm and it deals additional damage, also giving you attack speed & MR. That can give you enough MR against AP champs so you can farm up your cores before farming a Banshee's Veil.
I also like to add that you didn't take Ignite, which is too good for Xin. Your team didn't have ignite either, so their Tryndamere was safe the entire game. You don't take ghost & flash together. Pick one. I run with ghost since everything and everyone will die from a farmed Xin, you won't find yourself running away.