The build your using has some contradictions. Frozen Mallet and BORK are for chasing down your opponents and they both serve the same purpose. The slow from BORK will last long enough for you to kill whoever you're wanting to. If it takes you longer, they either flashed or you're already dead. BORK is also a "chase you down" thing, but Warrior / GB / Hydra all say one-shot. If your purpose is to one-shot, do not build Mallet and BORK. Instead, try these:

All of these items serve the one-shot build better than your current build.
What are your masteries?
Exchange AD for armor penetration, the scaling MR for scaling CDR. You don't want AD, since a majority of your ganks are post-6 and arpen does better damage as the game goes on (post-6). The same goes for CDR, since you want to be aggro. Having a level advantage means you have more health / resists than your opponent, and if this is true, the CDR is more important.